Equipment protecting enclosures

ABSTRACT

Biomass (e.g., plant biomass, animal biomass, and municipal waste biomass) is processed to produce useful intermediates and products, such as energy, fuels, foods or materials. For example, systems and methods are described that can be used to treat feedstock materials, such as cellulosic and/or lignocellulosic materials, in a vault in which the equipment is protected from radiation and hazardous gases by equipment enclosures. The equipment enclosures may be purged with gas.

This application is a continuation application of U.S. patentapplication Ser. No. 15/136,343, filed Apr. 22, 2016, which is acontinuation application of U.S. patent application Ser. No. 14/434,953,filed Apr. 10, 2015, now abandoned, which is a National Stage ofInternational Application No. PCT/US2013/064317, filed Oct. 10, 2013,which claims the benefit of U.S. Provisional Application Nos.61/711,801, filed on Oct. 10, 2012; 61/711,807, filed on Oct. 10, 2012;61/774,684, filed on Mar. 8, 2013; 61/774,773, filed on Mar. 8, 2013;61/774,731, filed on Mar. 8, 2013; 61/774,735, filed on Mar. 8, 2013;61/774,740, filed on Mar. 8, 2013; 61/774,744, filed on Mar. 8, 2013;61/774,746, filed on Mar. 8, 2013; 61/774,750, filed on Mar. 8, 2013;61/774,752, filed on Mar. 8, 2013; 61/774,754, filed on Mar. 8, 2013;61/774,775, filed on Mar. 8, 2013; 61/774,780, filed on Mar. 8, 2013;61/774,761, filed on Mar. 8, 2013; 61/774,723, filed on Mar. 8, 2013;and 61/793,336, filed on Mar. 15, 2013, all of which are herebyincorporated by reference in their entireties.

BACKGROUND OF THE INVENTION

Many potential lignocellulosic feedstocks are available today, includingagricultural residues, woody biomass, municipal waste, oilseeds/cakesand seaweed, to name a few. At present, these materials are oftenunder-utilized, being used, for example, as animal feed, biocompostmaterials, burned in a co-generation facility or even landfilled.

Lignocellulosic biomass includes crystalline cellulose fibrils embeddedin a hemicellulose matrix, surrounded by lignin. This produces a compactmatrix that is difficult to access by enzymes and other chemical,biochemical and/or biological processes. Cellulosic biomass materials(e.g., biomass material from which the lignin has been removed) is moreaccessible to enzymes and other conversion processes, but even so,naturally-occurring cellulosic materials often have low yields (relativeto theoretical yields) when contacted with hydrolyzing enzymes.Lignocellulosic biomass is even more recalcitrant to enzyme attack.Furthermore, each type of lignocellulosic biomass has its own specificcomposition of cellulose, hemicellulose and lignin.

SUMMARY

This invention relates to systems, methods and processing equipment usedfor producing products from a material, e.g., a biomass material.Generally, the methods include treating a recalcitrant biomass withelectron beams while conveying the material using one or more conveyorsin a vault and then biochemically and chemically processing the reducedrecalcitrance material to, for example, ethanol, xylitol and otherproducts. Radiation in the vault can cause damage to processingequipment in the vault or the radiation can create reactive gases, e.g.,ozone, which can also degrade processing equipment. This damage canpresent hazards due to equipment failure as well as incurring costs dueto down time and necessary repairs. Mitigation of this damage can beaccomplished by enclosing equipment and/or components of the processingequipment in equipment enclosures that are radiation opaque and that canbe purged with a gas that is inert to the components and/or equipment.

In one aspect the invention relates to a method of protecting processingequipment, e. g., material (e. g. biomass), biomass processingequipment, and other ancillary equipment that can be required forirradiation of biomass. The processing equipment can include, forexample, a vibratory conveyor for conveying a biomass material under anelectron beam and the associated equipment required for the conveyor,especially that which facilitates moving the biomass. This includes theequipment that provides the vibration for the conveyor. The ancillaryconveyor parts include all of the parts that are required for conveyingand, optionally, the vibratory part of the conveyor. The methods includeenclosing motor components of the vibratory conveyor in a substantiallyradiation opaque equipment enclosure (e.g., material including lead)while purging the equipment enclosure with a gas. The method can reducethe exposure of the motor to radiation as compared to the radiationexposure that would occur without the equipment enclosure. For example,the radiation exposure to the motors can be reduced by at least 10%, atleast 20%, at least 30%, at least 50%, at least 70% or even more (e.g.,at least 90%).

In some instances, the gas used in the methods can include, for example,air, oxygen reduced air, inert gases, nitrogen, argon, helium, carbondioxide, and mixtures of these. Optionally, the gas in the equipmentenclosure is exchanged at an exchange time of at least 10 minutes (e.g.,once every 5 minutes, once every minute, once every 30 seconds).

In some instances, the method further includes moving the equipmentenclosure, e.g., to access the motors, position the equipment enclosuresand/or adjust the equipment enclosure. The equipment enclosure can beconfigured to be movable (e.g., mounted on wheels, rails, sliders).Optionally, the method includes providing a gap between the equipmentenclosure and the vibratory conveyor to accommodate vibration ofcomponents of the vibratory conveyor during use and/or providing a pathfor air flow out of the equipment enclosures.

In some other instances, the method includes placing the biomassprocessing equipment inside a vault. For example, the method can includemethods wherein the vibratory conveyor is disposed within a vault. Inaddition and optionally the method can include methods wherein the vaultcontains irradiating equipment. Optionally the gas, for example, used topurge the equipment enclosures, is provided from within the vault. Forexample, gas that is provided from within the vault can be filtered ortreated prior to purging the equipment enclosures (e.g., to remove ozoneand/or destroy ozone).

In another aspect the invention relates to a system for protecting amotor e. g. a motor of a vibratory conveyor. The system can include avibratory conveyor having motor components mounted on a planar structureand a substantially radiation opaque equipment enclosure configured tobe positioned over the motor. The open end of the equipment enclosure isdimensioned so as to provide a circumferential gap between the equipmentenclosure and the planar structure when the equipment enclosure is inplace. Optionally, the gap is maintained by fixing the equipmentenclosure relative to the conveyor using a stop, a groove, a spacerand/or a fastener. The system can further include a conduit configuredfor flowing a purging gas into the equipment enclosure. Optionally, thesystem includes equipment for moving the equipment enclosure into andout of position over the components, for example, including wheelsattached to the equipment enclosure, tracks for sliding the equipmentenclosure, wheels disposed below the equipment enclosure (e.g., attachedto the ground), sliders (e.g., slide rails), linear guides andcombinations thereof. The motor components include the motor, supportstructures, conduits, piping, electrical components. This can includethe equipment required to move the enclosures.

In yet another aspect, the invention relates to a method of protectingbiomass processing equipment. The method includes conveying a material,such as a biomass material, e. g., a lignocellulosic material, through aradiation field, such as under an electron beam on a vibratory conveyor.The method further includes enclosing motor components e. g. motorcomponents of the conveyor, such as a vibratory conveyor, in asubstantially radiation opaque equipment enclosure. For additionalprotection, the equipment enclosure can be purged with a gas, such asair, nitrogen or combinations of these.

The equipment enclosures described are effective in protectingprocessing equipment/components utilized in radiation processing ofmaterials. The equipment enclosures also provide a volume within whichthe atmosphere can be easily controlled, e.g., exchanged or evacuatedfor ozone free air and/or other inert gases. The equipment enclosurescan be easy to construct and durable presenting an economical solutionto the incidental, accidental and or unintentional degradation ofprocessing equipment due to radiation.

Implementations of the invention can optionally include one or more ofthe following summarized features. In some implementations, the selectedfeatures can be applied or utilized in any order while in othersimplementations a specific selected sequence is applied or utilized.Individual features can be applied or utilized more than once in anysequence. In addition, an entire sequence, or a portion of a sequence,of applied or utilized features can be applied or utilized once orrepeatedly in any order. In some optional implementations, the featurescan be applied or utilized with different, or where applicable the same,set or varied, quantitative or qualitative parameters as determined by aperson skilled in the art. For example, parameters of the features suchas size, individual dimensions (e.g., length, width, height), locationof, degree (e.g., to what extent such as the degree of recalcitrance),duration, frequency of use, density, concentration, intensity and speedcan be varied or set, where applicable as determined by a person ofskill in the art.

Features, for example, include a method for protecting materialprocessing equipment, conveying a biomass material under an electronbeam on a conveyor, and enclosing motor components of the conveyor in aradiation opaque equipment enclosure e.g., while purging the enclosurewith a gas and where the gas can be air. The gas in the equipmentenclosure is exchanged at a rate of less than once every 10 minutes. Thegas used to purge the equipment enclosure may be air, oxygen reducedair, nitrogen, argon, helium, carbon dioxide, and mixtures thereof.

The conveyer for conveying the biomass is typically within a vault. Theirradiating equipment can also be in the vault. The gas that is used topurge the equipment enclosure can come from within the vault and it canbe filtered prior to using it in the equipment enclosure. The filtrationof the gas may include removal of ozone. There is also a conduitconfigured for flowing the purging gas into the equipment enclosure. Theconveyer can be a vibratory conveyor.

The equipment enclosure is movable such that there can be access to themotors such as the vibratory motors. The equipment enclosure and theconveyor are configured to accommodate movement of components when theconveyor is a vibratory conveyor and there can be a gap between theequipment enclosure and the vibratory conveyor equipment, especially themotor. The vibratory conveyor having motor components is mounted on astructure; such that when the equipment enclosure is in position toprotect the motor equipment there is gap provided between structure andthe equipment enclosure. This gap is maintained by fixing the equipmentenclosure relative to the conveyor using a stop, groove, spacer or afastener. In addition, equipment is provided to move the equipmentenclosure into and out of positions over the conveyor components. Theequipment to move the equipment enclosure may be wheels, tracks, sliderails, linear guides and combinations thereof.

The equipment enclosure can reduce the amount of radiation exposure theconveyer equipment gets by at least 10% when compared to no equipmentenclosure. Alternately, the reduction of radiation exposure may be atleast 20%, optionally at least 30%, or further optionally at least 50%and further at least 70% and alternatively at least 90% reduction inradiation exposure.

Other features and advantages of the invention will be apparent from thefollowing detailed description, and from the claims.

DESCRIPTION OF THE DRAWING

The foregoing will be apparent from the following more particulardescription of example embodiments of the invention, as illustrated inthe accompanying. The drawings are not necessarily to scale, emphasisinstead being placed upon illustrating embodiments of the presentinvention.

FIG. 1 is a perspective cutout view of a vault showing enclosures forprotecting components of biomass conveyors.

FIG. 2A is perspective view of a vibratory conveyor including equipmentenclosures for protecting motor components of the conveyor. FIGS. 2B and2C are detailed perspective views of an equipment enclosure.

FIG. 3A is a perspective view of a conduit. FIG. 3B is an axialcross-sectional view of the conduit. FIG. 3C is a radial cross-sectionalview of the conduit taken along line 3C-3C in FIG. 3A.

DETAILED DESCRIPTION

Using the methods and systems described herein, cellulosic andlignocellulosic feedstock material, for example that can be sourced frombiomass (e.g., plant biomass, animal biomass, paper, and municipal wastebiomass) and that are often readily available but difficult to process,can be turned into useful products (e.g., sugars such as xylose andglucose, and alcohols such as ethanol and butanol). Included are methodsand systems for treating biomass with radiation in which the processingequipment and/or components of the processing equipment are enclosed inradiation opaque equipment enclosures. In preferred implementations theequipment enclosures are purged with a gas that is inert to thecomponents and/or equipment.

Many processes for manufacturing sugar solutions and products derivedtherefrom are described herein. These processes may include, forexample, optionally mechanically treating a cellulosic and/orlignocellulosic feedstock. Before and/or after this treatment, thefeedstock can be treated with another physical treatment, for exampleirradiation, steam explosion, pyrolysis, sonication and/or oxidation toreduce, or further reduce its recalcitrance. A sugar solution is formedby saccharifying the feedstock by, for example, the addition of one ormore enzymes. A product can be derived from the sugar solution, forexample, by fermentation to an alcohol. Further processing can includepurifying the solution, for example by distillation. If desired, thesteps of measuring lignin content and setting or adjusting processparameters (e.g., irradiation dosage) based on this measurement can beperformed at various stages of the process, for example, as described inU.S. application Ser. No. 12/704,519, filed on Feb. 11, 2011, thecomplete disclosure of which is incorporated herein by reference.

Since the recalcitrance reducing treatment step can be a high energyprocess, the treatment can be performed in a vault and/or bunker tocontain the energy and/or some of the products derived from theenergetic process which can be hazardous. For example, the vault can beconfigured to contain heat energy, electrical energy (e.g., highvoltages, electric discharges), radiation energy (e.g., X-rays,accelerated particles, gamma-rays, ultraviolet radiation), explosionenergy (e.g., a shock wave, projectiles, blast wind), gases (e.g.,ozone, steam, nitrogen oxides and/or volatile organic compounds) andcombinations of these. Although this containment in a vault protectspeople and equipment outside of the vault, the equipment inside thevault is subjected to the energy and/or products derived from theenergetic process. In some cases, this containment by the vault canexacerbate the effects, for example by not allowing dissipation of gases(e.g., ozone, steam, nitrogen oxides and/or volatile organic compounds),or by providing reflective surfaces for the radiation, or the vault canprovide reflective surfaces for shock waves due to an explosion, or theenclosure can provide insulation causing the temperature in the vault tobe elevated. The interior of the vault during operation can therefore bea damaging environment. Hazards to humans are mitigated by ensuringno-one is in the vault during operation. Hazards to the equipment can bemitigated by enclosing the equipment or components of the equipment inprotective enclosures within the vault and/or bunker.

If treatment methods for reducing the recalcitrance include irradiationof the feedstock, for example, with ionizing radiation, unintentionalirradiation of equipment within the vault can occur. For example, anelectron beam striking a material can create X-rays through “breaking”radiation (Bremsstrahlung) that can also be ionizing depending on theirenergy. For example, irradiation of a biomass feedstock on a conveyorsurface made of a metal (e.g., stainless steel) would create X-rays,especially when the electrons strike the metal surface. The productionof X-rays when there is no biomass, or less than a sufficient amount ofbiomass to cover the conveyor surface, would be particularly strong, forexample during a startup, shutdown or when the process is operatingoutside of its normal parameters.

In addition, electron beams can produce ozone by the irradiation ofoxygen (e.g., oxygen present in air). Ozone is a strong oxidant with aredox potential of 2.07 V (vs. the Standard Hydrogen Electrode), higherthan other known strong oxidants such as hydrogen peroxide,permanganate, chlorine gas and hypochlorite with redox potentials of1.77V, 1.67V, 1.36V and 0.94V respectively. Therefore, materials, forexample, organic materials, are susceptible to degradation by ionizingradiation and oxidation by ozone. For example, the materials can degradethrough chain scission, cross-linking, oxidation and heating. Inaddition, metal components are susceptible to oxidation and degradationby ozone causing them, for example, to corrode/pit and/or rust.

Therefore, equipment that includes polymers and some metals (e.g.,excluding perhaps corrosion resistant or noble metals) can be damaged.For example, damage can occur to belts that include organic material,for example those used in equipment, e.g., as the coupling between adrive motor and an eccentric fly wheel of a vibratory conveyor.(Vibratory conveyors are described in U.S. Provisional Application Ser.No. 61/711,807 filed Oct. 10, 2012, the entire disclosure thereindescribed is herein by reference.) Systems and/or motor components thatcan be susceptible to damage by ozone and radiation include, forexample, wheels, bearings, springs, shock absorbers, solenoids,actuators, switches, gears, axles, washers, adhesives, fasteners, bolts,nuts, screws, brackets, frames, pulleys, covers, vibration dampeners,sliders, filters, vents, pistons, fans, fan blades, wires, wiresheathing, valves, drive shafts, computer chips, microprocessors,circuit boards and cables. Some organic materials that can be degradedby ionizing radiation and ozone include thermoplastics and thermosets.For example, organic materials that can be susceptible to damage includephenolics (e.g., Bakelite), fluorinated hydrocarbons (e.g., Teflon),thermoplastics, polyamides, polyesters, polyurethanes, rubbers (e.g.,butyl rubber, chlorinated polyethylene, polynorbornene), polyethers,polyethylene (Linear Low Density Polyethylene, High DensityPolyethylene), polystyrenes, polyvinyls (e.g., Poly Vinyl Chloride),cellulosics, Amino resins (e.g., Urea Formaldehyde), polyamines,polyurethanes, polyamides, Acrylics (e.g., Methyl Methacrylate), Acetals(e.g., Polyoxymethylene) lubricants (e.g., oils and gels), polysiloxanesand combinations of these.

To protect equipment that can include the above discussed materials orother materials or equipment described herein, the invention includesenclosing and/or shielding the materials from the radiation usingradiation opaque materials. In some implementations, the radiationopaque materials are selected to be capable of shielding the componentsfrom X-rays with high energy (short wavelength), which can penetratemany materials. One important factor in designing a radiation shieldingenclosure is the attenuation length of the materials used, which willdetermine the required thickness for a particular material, blend ofmaterials, or layered structure. The attenuation length is thepenetration distance at which the radiation is reduced to approximately1/e (e=Euler's number) times that of the incident radiation. Althoughvirtually all materials are radiation opaque if thick enough, materialscontaining a high compositional percentage (e.g., density) of elementsthat have a high Z value (atomic number) have a shorter radiationattenuation length and thus if such materials are used a thinner,lighter enclosure can be provided. Examples of high Z value materialsthat are used in radiation shielding are tantalum and lead. Anotherimportant parameter in radiation shielding is the halving distance,which is the thickness of a particular material that will reduce gammaray intensity by 50%. As an example for X-ray radiation with an energyof 0.1 MeV the halving thickness is about 15.1 mm for concrete and about0.27 mm for lead, while with an X-ray energy of 1 MeV the halvingthickness for concrete is about 44.45 mm and for lead is about 7.9 mm.Radiation opaque materials can be materials that are thick or thin solong as they can reduce the radiation that passes through to the otherside. Thus, if it is desired that a particular enclosure have a low wallthickness, e.g., for light weight or due to size constraints, thematerial chosen should have a sufficient Z value and/or attenuationlength so that its halving length is less than or equal to the desiredwall thickness of the enclosure.

In some cases, the radiation opaque material may be a layered material,for example having a layer of a higher Z value material, to provide goodshielding, and a layer of a lower Z value material to provide otherproperties (e.g., structural integrity, impact resistance, etc.). Insome cases, the layered material may be a “graded-Z” laminate, e.g.,including a laminate in which the layers provide a gradient from high-Zthrough successively lower-Z elements.

A radiation opaque material can reduce the radiation passing through astructure (e.g., a wall, door, ceiling, enclosure, a series of these orcombinations of these) formed of the material by about at least about10%, (e.g., at least about 20%, at least about 30%, at least about 40%,at least about 50%, at least about 60%, at least about 70%, at leastabout 80%, at least about 90%, at least about 95%, at least about 96%,at least about 97%, at least about 98%, at least about 99%, at leastabout 99.9%, at least about 99.99%, at least about 99.999%) as comparedto the incident radiation. Therefore, an equipment enclosure made of aradiation opaque material can reduce the exposure ofequipment/system/components by the same amount. Radiation opaquematerials can include stainless steel, metals with Z values above 25(e.g., lead, iron), concrete, dirt, sand and combinations thereof.Radiation opaque materials can include a barrier in the direction of theincident radiation of at least about 1 mm (e.g., 5 mm, 10 mm, 5 cm, 10cm, 100 cm, 1 m, 10 m).

The materials chosen to be radiation opaque can be chosen, along withtheir radiation attenuation properties, based on their other functions.For example, the walls of a vault that may support a heavy ceilingand/or equipment and may seldom if ever need to be moved, can beconstructed of concrete. A door to a vault would preferably be maderelatively thin and light and easy to open and close (e.g., hinged or ona track) and may be made of layers including iron and lead. Preferablythe enclosures for systems/equipment/components described herein wouldneed to be relatively small and movable. For example, they should bemovable by light equipment such as small fork lifts, motorized pulleys,or manually by a person. The weight should therefore be less than about2000 kg (e.g., less than about 1000 kg, less than about 900 kg, lessthan about 800 kg, less than about 700 kg, less than about 600 kg, lessthan about 500 kg, less than about 400 kg, less than about 300 kg, lessthan about 200 kg, less than about 100 kg, less than about 50 kg, lessthan about 25 kg). The construction can include lead, stainless steeland other metals with Z numbers above 25. The enclosures can includelayering of materials, for example lead and stainless steel, where leadcan provide radiation protection while stainless steel can providebetter structural properties.

In some cases the enclosures are mounted to be easily moved and/orremoved. For example, the enclosures can be mounted and/or suspended onwheels (e.g., casters), rails, pulleys and/or hinges. The enclosures canalso be partitioned where the partitions can be assembled ordisassembled from around the equipment/system/component to be enclosed.Part of the enclosure can be integrated with thesystem/equipment/component to be enclosed. For example, the equipmentmay be mounted on a plate that is protective and configured to mate withthe enclosure. The enclosures can be fastened to equipment, for example,by hooks, screws, bolts, straps, snaps, and/or other fasteners.

One or more enclosures can be used on a component, e.g., an innerenclosure surrounded by an outer (or several outer) enclosure(s). Theenclosures can be of any shape and can include walls that are curved,flat, rough, smooth, spherical and/or angled. The enclosure can includetubes and ducts. The enclosures can be configured to be combined, forexample to make a larger enclosure or to form different parts of anenclosure (e.g., a pipe can enclose part of the equipment, a boxenclosing a second part of the equipment).

To protect equipment including metals and organics as discussed abovefrom ozone, the enclosures for the equipment are configured to be purgedby a flowing gas that is ozone free, or has less ozone than would bepresent during an irradiation process. This purging is particularlyuseful in cases where the enclosure cannot be readily sealed around theitem to be protected, for example in the case of equipment that ismoving and/or vibrating, such as the motor of a vibratory conveyor. Inthis case, the presence of the purge gas in the equipment enclosureexcludes the entry of other gases (e.g., ozone) or particulates, whichcould otherwise enter the unsealed equipment enclosure. In someimplementations, each enclosure has one or more inlets for allowing apurging gas to enter, and one or more outlets for the purging gas toexit. The purging gas can be sourced from outside of a vault thatcontains the irradiation equipment, and may be, for example atmosphericair, air from a tank, nitrogen, argon, helium or combinations of these.The purging gas can optionally be sourced from within the vault,although preferably if vault air is utilized, the air should be treated,for example filtered through an ozone reducing filter (e.g., including acarbon filter). The flow of air should be sufficient to keep any ozonethat is present outside of the enclosure from entering the enclosure.For example, the exchange rate in the enclosure (the time it takes forthe volume of air entering and exiting the enclosure to equal the totalvolume of the enclosure) is, for example, less than about 10 min (e.g.,less than 9 min, less than 8 min, less than about 7 min, less than about6 min, less than about 5 min, less than about 4 min, less than about 3min, less than about 2 min, less than about 1 min, less than about 30seconds, less than about 10 seconds, less than about 1 second).Alternatively or additionally, pressure in the interior of the enclosurecan be slightly higher than the exterior, for example, by at least about0.0001% (e.g., at least about 0.001%, at least about 0.01%, at leastabout 0.1%, at least about 1%, at least about 10%, at least about 50%,at least about 100%). Alternatively or additionally the average flux ofthe purging gas at the outlet(s) of the enclosure is at least 0.1 mLcm-2sec-1 (e.g., at least about 0.5 mLcm-2 sec-1, at least about 1.0 mLcm-2sec-1, at least about 2.0 mLcm-2 sec-1, at least about 5.0 mLcm-2 sec-1,at least about 10 mLcm-2 sec-1, at least about 20 mLcm-2 sec-1, at leastabout 30 mLcm-2 sec-1, at least about 40 mLcm-2 sec-1, at least about 50mLcm-2 sec-1, at least about 60 mLcm-2 sec-1, at least about 70 mLcm-2sec-1, at least about 80 mLcm-2 sec-1, at least about 90 mLcm-2 sec-1,at least about 100 mLcm-2 sec-1).

In some embodiments the purge gas can be a cooling gas, for example, theflow providing cooling to motor components. For example, the gas can bechilled prior to being sent into the enclosure or can be from a cooledsource (e.g., liquid nitrogen blow off).

An embodiment of the invention is shown with reference to FIG. 1, whichis a perspective view of a vault with enclosures protecting mechanicalcomponents of conveyors. The ceiling/roof is not shown in this view sothat the interior of the vault can be more clearly seen. The boxes 112and 114 are positioned next to a first conveyor 116. The boxes 122 and124 are positioned next to a second conveyor 126. Conduits forelectrical cables and/or gas (e.g., air, nitrogen) to the boxes are alsoshown as tubes 118, 120, 128 and 130 extending downwards from theceiling. The tubes 118, 120, 128 and 130 pass through the ceiling. Theboxes and conduits are constructed of radiation opaque materials,protecting the components inside the box (e.g., the motors andassociated belts that drive the conveyors) from radiation and are bothexamples of enclosures for protecting equipment/systems and/orcomponents.

In use, biomass is conveyed into the vault and onto the first conveyortrough drop opening 140 connected to the outside of the vault by a tube(not shown) passing through the ceiling. The biomass travels in thedirection shown by the arrow and is dropped onto the second conveyor.The second conveyor coveys the biomass under the scanning horn 142. Thescanning horn is connected to a high vacuum electron conduit 144,through the ceiling, and to an electron accelerator 146. The electronaccelerator and power source 148 are supported by the roof of the vault.The atmosphere inside the vault contains elevated ozone levels due tothe electron irradiation of atmospheric oxygen during the process. Bypurging the boxes through their respective conduits with a fluid thatcontains less ozone than that in the vault atmosphere, ozone in thevicinity of the mechanical components for the conveyors is reduced. Thefluid can be, for example, atmospheric air, nitrogen, hydrogen, helium,vault air that has been treated to reduce the ozone level and mixturesof these. When the air that is used for purging the enclosures is vaultair that has been treated to reduce ozone, the conduit for the purginggas need not be passed through the roof and can be part of a systemincluding a pump and filter (e.g., an ozone filter) to remove the ozoneladen air and pump out (into the enclosure) ozone free air.

FIG. 2A is a figure of a vibratory conveyor 116 with boxes 114 and 112for covering mechanical components. The boxes are shown mounted on rails212 and 214 through wheels, for example 222 and 224. The boxes can bemoved on the rails in the directions indicted by the double headedarrow. In this view, the boxes are moved away from the conveyor, showingmotor component 232. Conduit for electrical and/or gas purging are shownas 118 and 120 attached to the conveyor. When the conveyor is inoperation, the boxes are pushed close to plates 250 and 251, enclosingthe motor component. Preferably the edge 258 of the box is not incontact with the plate since the friction caused by the oscillation ofthe conveyor (and attached plate) against the edge of the box when theconveyor is in operation, would cause wear and heating. X-rays are shownin an arbitrary location to the X-rays which are formed when theelectron beam strikes material, especially the surface of a metal suchas a conveyor that does not have biomass on it. In addition, the gapbetween the box edge and plate provides a flow path out of the equipmentenclosure so that the equipment enclosure can be purged. For example, anaverage gap between the edge and plate is preferably between 1 mm and 60mm (e.g., between about 1-5 mm, 1-10 mm, 1-20 mm, 1-30 mm, 1-40 mm, 2-10mm, 2-20 mm, 2-30 mm, 2-40 mm, 2-50 mm, 3-10 mm, 3-20 mm, 3-30 mm, 3-40mm, 3-50 mm, 4-10 mm, 4-20 mm, 4-30 mm, 4-40 mm, 4-50 mm, 5-10 mm, 5-20mm, 5-30 mm, 5-40 mm, 5-50 mm, 10-20 mm, 10-30 mm, 10-40 mm). The slots252 and 254 accommodate the conduits 118 and 120 respectively so thatthe box and plate can form an equipment enclosure with only a minimalgap (e.g., similar to the gap between the plate and box edge) betweenthe plates/conduits and boxes.

FIG. 2B is a close up view of box 114 in perspective showing the edge ofthe opening 258 for accepting vibratory conveyor components, e.g., amotor component. The rail 212 has stops 242 and 244 that can fix the boxat a desired position on the rails.

FIG. 2C is another perspective view of the boxes. The box includeshandles 262 and 264 that can be useful for gripping the boxes when theyneed to be moved.

In other embodiments, the gap between the equipment enclosure and thevibratory conveyor can be maintained by methods other than disclosedabove. For example, the equipment enclosure could be set into adepression configured to accept the footprint of the equipmentenclosure. Movable stops could be fixed by, for example friction orfasteners (e.g., pins, bolts), the floor and hold the equipmentenclosures in position. The equipment enclosure could have casters thatfit in a depression or set against stops. Magnetic stops can also beutilized. In some embodiments, the boxes could be suspended from theceiling or a wall by structures (e.g., ridged structures, steel frames,beams, wall depressions, cables, combinations of these) in the desiredposition. The equipment enclosures could even be mounted on the vibratorwhile leaving the gap by using spacers as well as fasteners. In someinstances, the equipment enclosures could be included as part of theconveyors, for example they could be covers for the motors that are madeof radiation opaque materials and have an inlet and vents for purgingwith a gas.

FIG. 3A is a perspective view of a conduit 118 showing a cable 312disposed therein. The can be an insulated electric cable for providingelectrical power and signals to a motor. The cable could also include amechanical cable, for example, for mechanically triggering a switch(e.g., emergency shut off). Although FIG. 3A shows only one cable,multiple cables and/or wires could be disposed in the conduit. FIGS. 3Band 3C are radial and axial cross-sectional views, respectively, of theconduit, showing the cable 312 in place within the internal cavity 314.The cable 312 runs through the conduit but does not fill the conduit sothat a flow of gas through the conduit can be accommodated as shown bythe arrows in FIG. 3B.

Radiation Treatment

The feedstock can be treated with electron bombardment to modify itsstructure to reduce its recalcitrance. Such treatment can, for example,reduce the average molecular weight of the feedstock, change thecrystalline structure of the feedstock, and/or increase the surface areaand/or porosity of the feedstock.

Electron bombardment via an electron beam is generally preferred,because it provides very high throughput. Electron beam accelerators areavailable, for example, from IBA, Belgium, and NHV Corporation, Japan.

Electron bombardment may be performed using an electron beam device thathas a nominal energy of less than 10 MeV, e.g., less than 7 MeV, lessthan 5 MeV, or less than 2 MeV, e.g., from about 0.5 to 1.5 MeV, fromabout 0.8 to 1.8 MeV, or from about 0.7 to 1 MeV. In someimplementations the nominal energy is about 500 to 800 keV.

The electron beam may have a relatively high total beam power (thecombined beam power of all accelerating heads, or, if multipleaccelerators are used, of all accelerators and all heads), e.g., atleast 25 kW, e.g., at least 30, 40, 50, 60, 65, 70, 80, 100, 125, or 150kW. In some cases, the power is even as high as 500 kW, 750 kW, or even1000 kW or more. In some cases, the electron beam has a beam power of1200 kW or more, e.g., 1400, 1600, 1800, or even 300 kW.

This high total beam power is usually achieved by utilizing multipleaccelerating heads. For example, the electron beam device may includetwo, four, or more accelerating heads. The use of multiple heads, eachof which has a relatively low beam power, prevents excessive temperaturerise in the material, thereby preventing burning of the material, andalso increases the uniformity of the dose through the thickness of thelayer of material.

It is generally preferred that the bed of biomass material has arelatively uniform thickness. In some embodiments, the thickness is lessthan about 1 inch (e.g., less than about 0.75 inches, less than about0.5 inches, less than about 0.25 inches, less than about 0.1 inches,between about 0.1 and 1 inch, between about 0.2 and 0.3 inches).

In some implementations, it is desirable to cool the material during andbetween dosing the material with electron bombardment. For example, thematerial can be cooled while it is conveyed, for example by a screwextruder, vibratory conveyor or other conveying equipment. For example,cooling while conveying is described in U.S. Provisional Application No.61/774,735 and U.S. Provisional Application No. 61/774,752 the entiredescription therein is herein incorporated by reference.

To reduce the energy required by the recalcitrance-reducing process, itis desirable to treat the material as quickly as possible. In general,it is preferred that treatment be performed at a dose rate of greaterthan about 0.25 Mrad per second, e.g., greater than about 0.5, 0.75, 1,1.5, 2, 5, 7, 10, 12, 15, or even greater than about 20 Mrad per second,e.g., about 0.25 to 2 Mrad per second. Higher dose rates allow a higherthroughput for a target (e.g., the desired) dose. Higher dose ratesgenerally require higher line speeds, to avoid thermal decomposition ofthe material. In one implementation, the accelerator is set for 3 MeV,50 mA beam current, and the line speed is 24 feet/minute, for a samplethickness of about 20 mm (e.g., comminuted corn cob material with a bulkdensity of 0.5 g/cm³).

In some embodiments, electron bombardment is performed until thematerial receives a total dose of at least 0.1 Mrad, 0.25 Mrad, 1 Mrad,5 Mrad, e.g., at least 10, 20, 30 or at least 40 Mrad. In someembodiments, the treatment is performed until the material receives adose of from about 10 Mrad to about 50 Mrad, e.g., from about 20 Mrad toabout 40 Mrad, or from about 25 Mrad to about 30 Mrad. In someimplementations, a total dose of 25 to 35 Mrad is preferred, appliedideally over a couple of seconds, e.g., at 5 Mrad/pass with each passbeing applied for about one second. Applying a dose of greater than 7 to8 Mrad/pass can in some cases cause thermal degradation of the feedstockmaterial. Cooling can be applied before, after, or during irradiation.For example, the cooling methods, systems and equipment as described inthe following applications can be utilized: U.S. Provisional ApplicationNo. 61/774,735 and U.S. Provisional Application No. 61/774,754 theentire disclosures of which are herein incorporated by reference.

Using multiple heads as discussed above, the material can be treated inmultiple passes, for example, two passes at 10 to 20 Mrad/pass, e.g., 12to 18 Mrad/pass, separated by a few seconds of cool-down, or threepasses of 7 to 12 Mrad/pass, e.g., 5 to 20 Mrad/pass, 10 to 40Mrad/pass, 9 to 11 Mrad/pass. As discussed herein, treating the materialwith several relatively low doses, rather than one high dose, tends toprevent overheating of the material and also increases dose uniformitythrough the thickness of the material. In some implementations, thematerial is stirred or otherwise mixed during or after each pass andthen smoothed into a uniform layer again before the next pass, tofurther enhance treatment uniformity.

In some embodiments, electrons are accelerated to, for example, a speedof greater than 75 percent of the speed of light, e.g., greater than 85,90, 95, or 99 percent of the speed of light.

In some embodiments, any processing described herein occurs onlignocellulosic material that remains dry as acquired or that has beendried, e.g., using heat and/or reduced pressure. For example, in someembodiments, the cellulosic and/or lignocellulosic material has lessthan about 25 wt. % retained water, measured at 25° C. and at fiftypercent relative humidity (e.g., less than about 20 wt. %, less thanabout 15 wt. %, less than about 14 wt. %, less than about 13 wt. %, lessthan about 12 wt. %, less than about 10 wt. %, less than about 9 wt. %,less than about 8 wt. %, less than about 7 wt. %, less than about 6 wt.%, less than about 5 wt. %, less than about 4 wt. %, less than about 3wt. %, less than about 2 wt. %, less than about 1 wt. %, less than about0.5 wt. %, less than about 15 wt. %.

In some embodiments, two or more electron sources are used, such as twoor more ionizing sources. For example, samples can be treated, in anyorder, with a beam of electrons, followed by gamma radiation and UVlight having wavelengths from about 100 nm to about 280 nm. In someembodiments, samples are treated with three ionizing radiation sources,such as a beam of electrons, gamma radiation, and energetic UV light.The biomass is conveyed through the treatment zone where it can bebombarded with electrons.

It may be advantageous to repeat the treatment to more thoroughly reducethe recalcitrance of the biomass and/or further modify the biomass. Inparticular the process parameters can be adjusted after a first (e.g.,second, third, fourth or more) pass depending on the recalcitrance ofthe material. In some embodiments, a conveyor can be used which includesa recirculating system where the biomass is conveyed multiple timesthrough the various processes described above. In some otherembodiments, multiple treatment devices (e.g., electron beam generators)are used to treat the biomass multiple (e.g., 2, 3, 4 or more) times. Inyet other embodiments, a single electron beam generator may be thesource of multiple beams (e.g., 2, 3, 4 or more beams) that can be usedfor treatment of the biomass.

The effectiveness in changing the molecular/supermolecular structureand/or reducing the recalcitrance of the carbohydrate-containing biomassdepends on the electron energy used and the dose applied, while exposuretime depends on the power and dose. In some embodiments, the dose rateand total dose are adjusted so as not to destroy (e.g., char or burn)the biomass material. For example, the carbohydrates should not bedamaged in the processing so that they can be released from the biomassintact, e.g. as monomeric sugars.

In some embodiments, the treatment (with any electron source or acombination of sources) is performed until the material receives a doseof at least about 0.05 Mrad, e.g., at least about 0.1, 0.25, 0.5, 0.75,1.0, 2.5, 5.0, 7.5, 10.0, 15, 20, 25, 30, 40, 50, 60, 70, 80, 90, 100,125, 150, 175, or 200 Mrad. In some embodiments, the treatment isperformed until the material receives a dose of between 0.1-100 Mrad,1-200, 5-200, 10-200, 5-150, 50-150 Mrad, 5-100, 5-50, 5-40, 10-50,10-75, 15-50, 20-35 Mrad.

In some embodiments, relatively low doses of radiation are utilized,e.g., to increase the molecular weight of a cellulosic orlignocellulosic material (with any radiation source or a combination ofsources described herein). For example, a dose of at least about 0.05Mrad, e.g., at least about 0.1 Mrad or at least about 0.25, 0.5, 0.75.1.0, 1.5, 2.0, 2.5, 3.0, 3.5, 4.0, or at least about 5.0 Mrad. In someembodiments, the irradiation is performed until the material receives adose of between 0.1 Mrad and 2.0 Mrad, e.g., between 0.5 rad and 4.0Mrad or between 1.0 Mrad and 3.0 Mrad.

It also can be desirable to irradiate from multiple directions,simultaneously or sequentially, in order to achieve a desired degree ofpenetration of radiation into the material. For example, depending onthe density and moisture content of the material, such as wood, and thetype of radiation source used (e.g., gamma or electron beam), themaximum penetration of radiation into the material may be only about0.75 inch. In such a cases, a thicker section (up to 1.5 inch) can beirradiated by first irradiating the material from one side, and thenturning the material over and irradiating from the other side.Irradiation from multiple directions can be particularly useful withelectron beam radiation, which irradiates faster than gamma radiationbut typically does not achieve as great a penetration depth.

Radiation Opaque Materials

The invention can include processing the material in a vault and/orbunker that is constructed using radiation opaque materials. In someimplementations, the radiation opaque materials are selected to becapable of shielding the components from X-rays with high energy (shortwavelength), which can penetrate many materials. One important factor indesigning a radiation shielding enclosure is the attenuation length ofthe materials used, which will determine the required thickness for aparticular material, blend of materials, or layered structure. Theattenuation length is the penetration distance at which the radiation isreduced to approximately 1/e (e=Euler's number) times that of theincident radiation. Although virtually all materials are radiationopaque if thick enough, materials containing a high compositionalpercentage (e.g., density) of elements that have a high Z value (atomicnumber) have a shorter radiation attenuation length and thus if suchmaterials are used a thinner, lighter shielding can be provided.Examples of high Z value materials that are used in radiation shieldingare tantalum and lead. Another important parameter in radiationshielding is the halving distance, which is the thickness of aparticular material that will reduce gamma ray intensity by 50%. As anexample for X-ray radiation with an energy of 0.1 MeV the halvingthickness is about 15.1 mm for concrete and about 0.27 mm for lead,while with an X-ray energy of 1 MeV the halving thickness for concreteis about 44.45 mm and for lead is about 7.9 mm. Radiation opaquematerials can be materials that are thick or thin so long as they canreduce the radiation that passes through to the other side. Thus, if itis desired that a particular enclosure have a low wall thickness, e.g.,for light weight or due to size constraints, the material chosen shouldhave a sufficient Z value and/or attenuation length so that its halvinglength is less than or equal to the desired wall thickness of theenclosure.

In some cases, the radiation opaque material may be a layered material,for example having a layer of a higher Z value material, to provide goodshielding, and a layer of a lower Z value material to provide otherproperties (e.g., structural integrity, impact resistance, etc.). Insome cases, the layered material may be a “graded-Z” laminate, e.g.,including a laminate in which the layers provide a gradient from high-Zthrough successively lower-Z elements. In some cases, the radiationopaque materials can be interlocking blocks, for example, lead and/orconcrete blocks can be supplied by NELCO Worldwide (Burlington, Mass.),and reconfigurable vaults can be utilized as described in U.S.Provisional Application No. 61/774,744.

A radiation opaque material can reduce the radiation passing through astructure (e.g., a wall, door, ceiling, enclosure, a series of these orcombinations of these) formed of the material by about at least about10%, (e.g., at least about 20%, at least about 30%, at least about 40%,at least about 50%, at least about 60%, at least about 70%, at leastabout 80%, at least about 90%, at least about 95%, at least about 96%,at least about 97%, at least about 98%, at least about 99%, at leastabout 99.9%, at least about 99.99%, at least about 99.999%) as comparedto the incident radiation. Therefore, an enclosure made of a radiationopaque material can reduce the exposure of equipment/system/componentsby the same amount. Radiation opaque materials can include stainlesssteel, metals with Z values above 25 (e.g., lead, iron), concrete, dirt,sand and combinations thereof. Radiation opaque materials can include abarrier in the direction of the incident radiation of at least about 1mm (e.g., 5 mm, 10 mm, 5 cm, 10 cm, 100 cm, 1 m, 10 m).

Radiation Sources

The type of radiation determines the kinds of radiation sources used aswell as the radiation devices and associated equipment. The methods,systems and equipment described herein, for example for treatingmaterials with radiation, can utilized sources as described herein aswell as any other useful source.

Sources of gamma rays include radioactive nuclei, such as isotopes ofcobalt, calcium, technicium, chromium, gallium, indium, iodine, iron,krypton, samarium, selenium, sodium, thalium, and xenon.

Sources of X-rays include electron beam collision with metal targets,such as tungsten or molybdenum or alloys, or compact light sources, suchas those produced commercially by Lyncean.

Alpha particles are identical to the nucleus of a helium atom and areproduced by the alpha decay of various radioactive nuclei, such asisotopes of bismuth, polonium, astatine, radon, francium, radium,several actinides, such as actinium, thorium, uranium, neptunium,curium, californium, americium, and plutonium.

Sources for ultraviolet radiation include deuterium or cadmium lamps.

Sources for infrared radiation include sapphire, zinc, or selenidewindow ceramic lamps.

Sources for microwaves include klystrons, Slevin type RF sources, oratom beam sources that employ hydrogen, oxygen, or nitrogen gases.

Accelerators used to accelerate the particles (e.g., electrons or ions)can be electrostatic DC, e. g. electrodynamic DC, RF linear, magneticinduction linear or continuous wave. For example, various irradiatingdevices may be used in the methods disclosed herein, including fieldionization sources, electrostatic ion separators, field ionizationgenerators, thermionic emission sources, microwave discharge ionsources, recirculating or static accelerators, dynamic linearaccelerators, van de Graaff accelerators, Cockroft Walton accelerators(e.g., PELLETRON® accelerators), LINACS, Dynamitrons (e.g, DYNAMITRON®accelerators), cyclotrons, synchrotrons, betatrons, transformer-typeaccelerators, microtrons, plasma generators, cascade accelerators, andfolded tandem accelerators. For example, cyclotron type accelerators areavailable from IBA, Belgium, such as the RHODOTRON™ system, while DCtype accelerators are available from RDI, now IBA Industrial, such asthe DYNAMITRON®. Other suitable accelerator systems include, forexample: DC insulated core transformer (ICT) type systems, availablefrom Nissin High Voltage, Japan; S-band LINACs, available from L3-PSD(USA), Linac Systems (France), Mevex (Canada), and Mitsubishi HeavyIndustries (Japan); L-band LINACs, available from Iotron Industries(Canada); and ILU-based accelerators, available from Budker Laboratories(Russia). Ions and ion accelerators are discussed in IntroductoryNuclear Physics, Kenneth S. Krane, John Wiley & Sons, Inc. (1988), KrstoPrelec, FIZIKA B 6 (1997) 4, 177-206, Chu, William T., “Overview ofLight-Ion Beam Therapy”, Columbus-Ohio, ICRU-IAEA Meeting, 18-20 Mar.2006, Iwata, Y. et al., “Alternating-Phase-Focused IH-DTL for Heavy-IonMedical Accelerators”, Proceedings of EPAC 2006, Edinburgh, Scotland,and Leitner, C. M. et al., “Status of the Superconducting ECR Ion SourceVenus”, Proceedings of EPAC 2000, Vienna, Austria. Some particleaccelerators and their uses are disclosed, for example, in U.S. Pat. No.7,931,784 to Medoff, the complete disclosure of which is incorporatedherein by reference.

Electrons may be produced by radioactive nuclei that undergo beta decay,such as isotopes of iodine, cesium, technetium, and iridium.Alternatively, an electron gun can be used as an electron source viathermionic emission and accelerated through an accelerating potential.An electron gun generates electrons, which are then accelerated througha large potential (e.g., greater than about 500 thousand, greater thanabout lmillion, greater than about 2 million, greater than about 5million, greater than about 6 million, greater than about 7 million,greater than about 8 million, greater than about 9 million, or evengreater than 10 million volts) and then scanned magnetically in the x-yplane, where the electrons are initially accelerated in the z directiondown the accelerator tube and extracted through a foil window. Scanningthe electron beams is useful for increasing the irradiation surface whenirradiating materials, e.g., a biomass, that is conveyed through thescanned beam. Scanning the electron beam also distributes the thermalload homogenously on the window and helps reduce the foil window rupturedue to local heating by the electron beam. Window foil rupture is acause of significant down-time due to subsequent necessary repairs andre-starting the electron gun.

A beam of electrons can be used as the radiation source. A beam ofelectrons has the advantages of high dose rates (e.g., 1, 5, or even 10Mrad per second), high throughput, less containment, and lessconfinement equipment. Electron beams can also have high electricalefficiency (e.g., 80%), allowing for lower energy usage relative toother radiation methods, which can translate into a lower cost ofoperation and lower greenhouse gas emissions corresponding to thesmaller amount of energy used. Electron beams can be generated, e.g., byelectrostatic generators, cascade generators, transformer generators,low energy accelerators with a scanning system, low energy acceleratorswith a linear cathode, linear accelerators, and pulsed accelerators.

Electrons can also be more efficient at causing changes in the molecularstructure of carbohydrate-containing materials, for example, by themechanism of chain scission. In addition, electrons having energies of0.5-10 MeV can penetrate low density materials, such as the biomassmaterials described herein, e.g., materials having a bulk density ofless than 0.5 g/cm3, and a depth of 0.3-10 cm. Electrons as an ionizingradiation source can be useful, e.g., for relatively thin piles, layersor beds of materials, e.g., less than about 0.5 inch, e.g., less thanabout 0.4 inch, 0.3 inch, 0.25 inch, or less than about 0.1 inch. Insome embodiments, the energy of each electron of the electron beam isfrom about 0.3 MeV to about 2.0 MeV (million electron volts), e.g., fromabout 0.5 MeV to about 1.5 MeV, or from about 0.7 MeV to about 1.25 MeV.Methods of irradiating materials are discussed in U.S. Pat. App. Pub.2012/0100577 A1, filed Oct. 18, 2011, the entire disclosure of which isherein incorporated by reference.

Electron beam irradiation devices may be procured commercially or built.For example elements or components such inductors, capacitors, casings,power sources, cables, wiring, voltage control systems, current controlelements, insulating material, microcontrollers and cooling equipmentcan be purchased and assembled into a device. Optionally, a commercialdevice can be modified and/or adapted. For example, devices andcomponents can be purchased from any of the commercial sources describedherein including Ion Beam Applications (Louvain-la-Neuve, Belgium), NHVCorporation (Japan), the Titan Corporation (San Diego, Calif.), ViviradHigh Voltage Corp (Billeric, MA) and/or Budker Laboratories (Russia).Typical electron energies can be 0.5 MeV, 1 MeV, 2 MeV, 4.5 MeV, 7.5MeV, or 10 MeV. Typical electron beam irradiation device power can be 1kW, 5 kW, 10 kW, 20 kW, 50 kW, 60 kW, 70 kW, 80 kW, 90 kW, 100 kW, 125kW, 150 kW, 175 kW, 200 kW, 250 kW, 300 kW, 350 kW, 400 kW, 450 kW, 500kW, 600 kW, 700 kW, 800 kW, 900 kW or even 1000 kW. Accelerators thatcan be used include NHV irradiators medium energy series EPS-500 (e.g.,500 kV accelerator voltage and 65, 100 or 150 mA beam current), EPS-800(e.g., 800 kV accelerator voltage and 65 or 100 mA beam current), orEPS-1000 (e.g., 1000 kV accelerator voltage and 65 or 100 mA beamcurrent). Also, accelerators from NHV's high energy series can be usedsuch as EPS-1500 (e.g., 1500 kV accelerator voltage and 65 mA beamcurrent), EPS-2000 (e.g., 2000 kV accelerator voltage and 50 mA beamcurrent), EPS-3000 (e.g., 3000 kV accelerator voltage and 50 mA beamcurrent) and EPS-5000 (e.g., 5000 and 30 mA beam current).

Tradeoffs in considering electron beam irradiation device powerspecifications include cost to operate, capital costs, depreciation, anddevice footprint. Tradeoffs in considering exposure dose levels ofelectron beam irradiation would be energy costs and environment, safety,and health (ESH) concerns. Typically, generators are housed in a vault,e.g., of lead or concrete, especially for production from X-rays thatare generated in the process. Tradeoffs in considering electron energiesinclude energy costs.

The electron beam irradiation device can produce either a fixed beam ora scanning beam. A scanning beam may be advantageous with large scansweep length and high scan speeds, as this would effectively replace alarge, fixed beam width. Further, available sweep widths of 0.5 m, 1 m,2 m or more are available. The scanning beam is preferred in mostembodiments describe herein because of the larger scan width and reducedpossibility of local heating and failure of the windows.

Electron Guns—Windows

The extraction system for an electron accelerator can include two windowfoils. Window foils are described in U.S. Provisional Application Ser.No. 61/711,801 filed Oct. 10, 2012 the complete disclosure of which isherein incorporated by reference. The cooling gas in the two foil windowextraction system can be a purge gas or a mixture, for example air, or apure gas. In one embodiment the gas is an inert gas such as nitrogen,argon, helium and or carbon dioxide. It is preferred to use a gas ratherthan a liquid since energy losses to the electron beam are minimized.Mixtures of pure gas can also be used, either pre-mixed or mixed in lineprior to impinging on the windows or in the space between the windows.The cooling gas can be cooled, for example, by using a heat exchangesystem (e.g., a chiller) and/or by using boil off from a condensed gas(e.g., liquid nitrogen, liquid helium).

When using a conveyor enclosure, the enclosed conveyor can also bepurged with an inert gas so as to maintain an atmosphere at a reducedoxygen level. Keeping oxygen levels low avoids the formation of ozonewhich in some instances is undesirable due to its reactive and toxicnature. For example, the oxygen can be less than about 20% (e.g., lessthan about 10%, less than about 1%, less than about 0.1%, less thanabout 0.01%, or even less than about 0.001% oxygen). Purging can be donewith an inert gas including, but not limited to, nitrogen, argon, heliumor carbon dioxide. This can be supplied, for example, from a boil off ofa liquid source (e.g., liquid nitrogen or helium), generated orseparated from air in situ, or supplied from tanks. The inert gas can berecirculated and any residual oxygen can be removed using a catalyst,such as a copper catalyst bed. Alternatively, combinations of purging,recirculating and oxygen removal can be done to keep the oxygen levelslow.

The conveyor enclosure can also be purged with a reactive gas that canreact with the biomass. This can be done before, during or after theirradiation process. The reactive gas can be, but is not limited to,nitrous oxide, ammonia, oxygen, ozone, hydrocarbons, aromatic compounds,amides, peroxides, azides, halides, oxyhalides, phosphides, phosphines,arsines, sulfides, thiols, boranes and/or hydrides. The reactive gas canbe activated in the conveyor enclosure, e.g., by irradiation (e.g.,electron beam, UV irradiation, microwave irradiation, heating, IRradiation), so that it reacts with the biomass. The biomass itself canbe activated, for example by irradiation. Preferably the biomass isactivated by the electron beam, to produce radicals which then reactwith the activated or unactivated reactive gas, e.g., by radicalcoupling or quenching.

Purging gases supplied to an enclosed conveyor can also be cooled, forexample below about 25° C., below about 0° C., below about −40° C.,below about −80° C., below about −120° C. For example, the gas can beboiled off from a compressed gas such as liquid nitrogen or sublimedfrom solid carbon dioxide. As an alternative example, the gas can becooled by a chiller or part of or the entire conveyor can be cooled.

Heating and Throughput During Radiation Treatment

Several processes can occur in biomass when electrons from an electronbeam interact with matter in inelastic collisions. For example,ionization of the material, chain scission of polymers in the material,cross linking of polymers in the material, oxidation of the material,generation of X-rays (“Bremsstrahlung”) and vibrational excitation ofmolecules (e.g. phonon generation). Without being bound to a particularmechanism, the reduction in recalcitrance can be due to several of theseinelastic collision effects, for example ionization, chain scission ofpolymers, oxidation and phonon generation. Some of the effects (e.g.,especially X-ray generation), necessitate shielding and engineeringbarriers, for example, enclosing the irradiation processes in a concrete(or other radiation opaque material) vault. Another effect ofirradiation, vibrational excitation, is equivalent to heating up thesample. Heating the sample by irradiation can help in recalcitrancereduction, but excessive heating can destroy the material, as will beexplained below.

The adiabatic temperature rise (ΔT) from adsorption of ionizingradiation is given by the equation: ΔT=D/Cp: where D is the average dosein kGy, Cp is the heat capacity in J/g ° C., and ΔT is the change intemperature in ° C. A typical dry biomass material will have a heatcapacity close to 2. Wet biomass will have a higher heat capacitydependent on the amount of water since the heat capacity of water isvery high (4.19 J/g ° C.). Metals have much lower heat capacities, forexample 304 stainless steel has a heat capacity of 0.5 J/g ° C. Thetemperature change due to the instant adsorption of radiation in abiomass and stainless steel for various doses of radiation is shown inTable 1.

TABLE 1 Calculated Temperature increase for biomass and stainless steel.Dose (Mrad) Estimated Biomass ΔT (° C.) Steel ΔT (° C.) 10 50 200 50 2501000 100 500 2000 150 750 3000 200 1000 4000

High temperatures can destroy and or modify the biopolymers in biomassso that the polymers (e.g., cellulose) are unsuitable for furtherprocessing. A biomass subjected to high temperatures can become dark,sticky and give off odors indicating decomposition. The stickiness caneven make the material hard to convey. The odors can be unpleasant andbe a safety issue. In fact, keeping the biomass below about 200° C. hasbeen found to be beneficial in the processes described herein (e.g.,below about 190° C., below about 180° C., below about 170° C., belowabout 160° C., below about 150° C., below about 140° C., below about130° C., below about 120° C., below about 110° C., between about 60° C.and 180° C., between about 60° C. and 160° C., between about 60° C. and150° C., between about 60° C. and 140° C., between about 60° C. and 130°C., between about 60° C. and 120° C., between about 80° C. and 180° C.,between about 100° C. and 180° C., between about 120° C. and 180° C.,between about 140° C. and 180° C., between about 160° C. and 180° C.,between about 100° C. and 140° C., between about 80° C. and 120° C.).

It has been found that irradiation above about 10 Mrad is desirable forthe processes described herein (e.g., reduction of recalcitrance). Ahigh throughput is also desirable so that the irradiation does notbecome a bottle neck in processing the biomass. The treatment isgoverned by a Dose rate equation: M=FP/D*time, where M is the mass ofirradiated material (Kg), F is the fraction of power that is adsorbed(unit less), P is the emitted power (kW=Voltage in MeV*Current in mA),time is the treatment time (sec) and D is the adsorbed dose (kGy). In anexemplary process where the fraction of adsorbed power is fixed, thePower emitted is constant and a set dosage is desired, the throughput(e.g., M, the biomass processed) can be increased by increasing theirradiation time. However, increasing the irradiation time withoutallowing the material to cool, can excessively heat the material asexemplified by the calculations shown above. Since biomass has a lowthermal conductivity (less than about 0.1 Wm⁻¹K⁻¹), heat dissipation isslow, unlike, for example metals (greater than about 10 Wm⁻¹K⁻¹) whichcan dissipate energy quickly as long as there is a heat sink to transferthe energy to.

Electron Guns—Beam Stops

In some embodiments the systems and methods include a beam stop (e.g., ashutter). For example, the beam stop can be used to quickly stop orreduce the irradiation of material without powering down the electronbeam device. Alternatively, the beam stop can be used while powering upthe electron beam, e.g., the beam stop can stop the electron beam untila beam current of a desired level is achieved. The beam stop can beplaced between the primary foil window and secondary foil window. Forexample, the beam stop can be mounted so that it is movable, that is, sothat it can be moved into and out of the beam path. Even partialcoverage of the beam can be used, for example, to control the dose ofirradiation. The beam stop can be mounted to the floor, to a conveyorfor the biomass, to a wall, to the radiation device (e.g., at the scanhorn), or to any structural support. Preferably the beam stop is fixedin relation to the scan horn so that the beam can be effectivelycontrolled by the beam stop. The beam stop can incorporate a hinge, arail, wheels, slots, or other means allowing for its operation in movinginto and out of the beam. The beam stop can be made of any material thatwill stop at least 5% of the electrons, e.g., at least 10%, 20%, 30%,40%, 50%, 60%, 70%, at least 80%, 85%, 90%, 91%, 92%, 93%, 94%, 95%,96%, 97%, 98%, 99% or even about 100% of the electrons.

The beam stop can be made of a metal including, but not limited to,stainless steel, lead, iron, molybdenum, silver, gold, titanium,aluminum, tin, or alloys of these, or laminates (layered materials) madewith such metals (e.g., metal-coated ceramic, metal-coated polymer,metal-coated composite, multilayered metal materials).

The beam stop can be cooled, for example, with a cooling fluid such asan aqueous solution or a gas. The beam stop can be partially orcompletely hollow, for example with cavities. Interior spaces of thebeam stop can be used for cooling fluids and gases. The beam stop can beof any shape, including flat, curved, round, oval, square, rectangular,beveled and wedged shapes.

The beam stop can have perforations so as to allow some electronsthrough, thus controlling (e.g., reducing) the levels of radiationacross the whole area of the window, or in specific regions of thewindow. The beam stop can be a mesh formed, for example, from fibers orwires. Multiple beam stops can be used, together or independently, tocontrol the irradiation. The beam stop can be remotely controlled, e.g.,by radio signal or hard wired to a motor for moving the beam into or outof position.

Beam Dumps

The embodiments disclosed herein can also include a beam dump. A beamdump's purpose is to safely absorb a beam of charged particles. Like abeam stop, a beam dump can be used to block the beam of chargedparticles. However, a beam dump is much more robust than a beam stop,and is intended to block the full power of the electron beam for anextended period of time. They are often used to block the beam as theaccelerator is powering up.

Beam dumps are also designed to accommodate the heat generated by suchbeams, and are usually made from materials such as copper, aluminum,carbon, beryllium, tungsten, or mercury. Beam dumps can be cooled, forexample by using a cooling fluid that is in thermal contact with thebeam dump.

Biomass Materials

Lignocellulosic materials include, but are not limited to, wood,particle board, forestry wastes (e.g., sawdust, aspen wood, wood chips),grasses, (e.g., switchgrass, miscanthus, cord grass, reed canary grass),grain residues, (e.g., rice hulls, oat hulls, wheat chaff, barleyhulls), agricultural waste (e.g., silage, canola straw, wheat straw,barley straw, oat straw, rice straw, jute, hemp, flax, bamboo, sisal,abaca, corn cobs, corn stover, soybean stover, corn fiber, alfalfa, hay,coconut hair), sugar processing residues (e.g., bagasse, beet pulp,agave bagasse), algae, seaweed, manure, sewage, and mixtures of any ofthese.

In some cases, the lignocellulosic material includes corncobs. Ground orhammer milled corncobs can be spread in a layer of relatively uniformthickness for irradiation, and after irradiation are easy to disperse inthe medium for further processing. To facilitate harvest and collection,in some cases the entire corn plant is used, including the corn stalk,corn kernels, and in some cases even the root system of the plant.

Advantageously, no additional nutrients (other than a nitrogen source,e.g., urea or ammonia) are required during fermentation of corncobs orcellulosic or lignocellulosic materials containing significant amountsof corncobs.

Corncobs, before and after comminution, are also easier to convey anddisperse, and have a lesser tendency to form explosive mixtures in airthan other cellulosic or lignocellulosic materials such as hay andgrasses.

Cellulosic materials include, for example, paper, paper products, paperwaste, paper pulp, pigmented papers, loaded papers, coated papers,filled papers, magazines, printed matter (e.g., books, catalogs,manuals, labels, calendars, greeting cards, brochures, prospectuses,newsprint), printer paper, polycoated paper, card stock, cardboard,paperboard, materials having a high α-cellulose content such as cotton,and mixtures of any of these. For example paper products as described inU.S. application Ser. No. 13/396,365 (“Magazine Feedstocks” by Medoff etal., filed Feb. 14, 2012), the full disclosure of which is incorporatedherein by reference.

Cellulosic materials can also include lignocellulosic materials whichhave been partially or fully de-lignified.

In some instances other biomass materials can be utilized, for examplestarchy materials. Starchy materials include starch itself, e.g., cornstarch, wheat starch, potato starch or rice starch, a derivative ofstarch, or a material that includes starch, such as an edible foodproduct or a crop. For example, the starchy material can be arracacha,buckwheat, banana, barley, cassava, kudzu, oca, sago, sorghum, regularhousehold potatoes, sweet potato, taro, yams, or one or more beans, suchas favas, lentils or peas. Blends of any two or more starchy materialsare also starchy materials. Mixtures of starchy, cellulosic and orlignocellulosic materials can also be used. For example, a biomass canbe an entire plant, a part of a plant or different parts of a plant,e.g., a wheat plant, cotton plant, a corn plant, rice plant or a tree.The starchy materials can be treated by any of the methods describedherein.

Microbial materials include, but are not limited to, any naturallyoccurring or genetically modified microorganism or organism thatcontains or is capable of providing a source of carbohydrates (e.g.,cellulose), for example, protists, e.g., animal protists (e.g., protozoasuch as flagellates, amoeboids, ciliates, and sporozoa) and plantprotists (e.g., algae such alveolates, chlorarachniophytes,cryptomonads, euglenids, glaucophytes, haptophytes, red algae,stramenopiles, and viridaeplantae). Other examples include seaweed,plankton (e.g., macroplankton, mesoplankton, microplankton,nanoplankton, picoplankton, and fem

toplankton), phytoplankton, bacteria (e.g., gram positive bacteria, gramnegative bacteria, and extremophiles), yeast and/or mixtures of these.In some instances, microbial biomass can be obtained from naturalsources, e.g., the ocean, lakes, bodies of water, e.g., salt water orfresh water, or on land. Alternatively or in addition, microbial biomasscan be obtained from culture systems, e.g., large scale dry and wetculture and fermentation systems.

In other embodiments, the biomass materials, such as cellulosic, starchyand lignocellulosic feedstock materials, can be obtained from transgenicmicroorganisms and plants that have been modified with respect to a wildtype variety. Such modifications may be, for example, through theiterative steps of selection and breeding to obtain desired traits in aplant. Furthermore, the plants can have had genetic material removed,modified, silenced and/or added with respect to the wild type variety.For example, genetically modified plants can be produced by recombinantDNA methods, where genetic modifications include introducing ormodifying specific genes from parental varieties, or, for example, byusing transgenic breeding wherein a specific gene or genes areintroduced to a plant from a different species of plant and/or bacteria.Another way to create genetic variation is through mutation breedingwherein new alleles are artificially created from endogenous genes. Theartificial genes can be created by a variety of ways including treatingthe plant or seeds with, for example, chemical mutagens (e.g., usingalkylating agents, epoxides, alkaloids, peroxides, formaldehyde),irradiation (e.g., X-rays, gamma rays, neutrons, beta particles, alphaparticles, protons, deuterons, UV radiation) and temperature shocking orother external stressing and subsequent selection techniques. Othermethods of providing modified genes is through error prone PCR and DNAshuffling followed by insertion of the desired modified DNA into thedesired plant or seed. Methods of introducing the desired geneticvariation in the seed or plant include, for example, the use of abacterial carrier, biolistics, calcium phosphate precipitation,electroporation, gene splicing, gene silencing, lipofection,microinjection and viral carriers. Additional genetically modifiedmaterials have been described in U.S. application Ser. No. 13/396,369filed Feb. 14, 2012 the full disclosure of which is incorporated hereinby reference.

Any of the methods described herein can be practiced with mixtures ofany biomass materials described herein.

Other Materials

Other materials (e.g., natural or synthetic materials), for examplepolymers, can be treated and/or made utilizing the methods, equipmentand systems described herein. For example, polyethylene (e.g., linearlow density ethylene and high density polyethylene), polystyrenes,sulfonated polystyrenes, poly (vinyl chloride), polyesters (e.g.,nylons, Dacron™, Kodel™), polyalkylene esters, poly vinyl esters,polyamides (e.g., Kevlar™), polyethylene terephthalate, celluloseacetate, acetal, poly acrylonitrile, polycarbonates(Lexan™), acrylics[e.g., poly (methyl methacrylate), poly(methyl methacrylate),polyacrylnitriles, Polyurethanes, polypropylene, poly butadiene,polyisobutylene, polyacrylonitrile, polychloroprene (e.g. neoprene),poly(cis-1,4-isoprene) [e.g., natural rubber], poly(trans-1,4-isoprene)[e.g., gutta percha], phenol formaldehyde, melamine formaldehyde,epoxides, polyesters, poly amines, polycarboxylic acids, polylacticacids, polyvinyl alcohols, polyanhydrides, poly fluoro carbons (e.g.,Teflon™), silicons (e.g., silicone rubber), polysilanes, poly ethers(e.g., polyethylene oxide, polypropylene oxide), waxes, oils andmixtures of these. Also included are plastics, rubbers, elastomers,fibers, waxes, gels, oils, adhesives, thermoplastics, thermosets,biodegradable polymers, resins made with these polymers, other polymers,other materials and combinations thereof. The polymers can be made byany useful method including cationic polymerization, anionicpolymerization, radical polymerization, metathesis polymerization, ringopening polymerization, graft polymerization, addition polymerization.In some cases the treatments disclosed herein can be used, for example,for radically initiated graft polymerization and cross linking.Composites of polymers, for example with glass, metals, biomass (e.g.,fibers, particles), ceramics can also be treated and/or made.

Other materials that can be treated by using the methods, systems andequipment disclosed herein are ceramic materials, minerals, metals,inorganic compounds. For example, silicon and germanium crystals,silicon nitrides, metal oxides, semiconductors, insulators, cements andor conductors.

In addition, manufactured multipart or shaped materials (e.g., molded,extruded, welded, riveted, layered or combined in any way) can betreated, for example cables, pipes, boards, enclosures, integratedsemiconductor chips, circuit boards, wires, tires, windows, laminatedmaterials, gears, belts, machines, combinations of these. For example,treating a material by the methods described herein can modify thesurfaces, for example, making them susceptible to furtherfunctionalization, combinations (e.g., welding) and/or treatment cancross link the materials.

Biomass Material Preparation—Mechanical Treatments

The biomass can be in a dry form, for example with less than about 35%moisture content (e.g., less than about 20%, less than about 15%, lessthan about 10% less than about 5%, less than about 4%, less than about3%, less than about 2% or even less than about 1%). The biomass can alsobe delivered in a wet state, for example as a wet solid, a slurry or asuspension with at least about 10 wt. % solids (e.g., at least about 20wt. %, at least about 30 wt. %, at least about 40 wt. %, at least about50 wt. %, at least about 60 wt. %, at least about 70 wt. %).

The processes disclosed herein can utilize low bulk density materials,for example cellulosic or lignocellulosic feedstocks that have beenphysically pretreated to have a bulk density of less than about 0.75g/cm3, e.g., less than about 0.7, 0.65, 0.60, 0.50, 0.35, 0.25, 0.20,0.15, 0.10, 0.05 or less, e.g., less than about 0.025 g/cm3. Bulkdensity is determined using ASTM D1895B. Briefly, the method involvesfilling a measuring cylinder of known volume with a sample and obtaininga weight of the sample. The bulk density is calculated by dividing theweight of the sample in grams by the known volume of the cylinder incubic centimeters. If desired, low bulk density materials can bedensified, for example, by methods described in U.S. Pat. No. 7,971,809to Medoff, the full disclosure of which is hereby incorporated byreference. In some cases, the pre-treatment processing includesscreening of the biomass material. Screening can be through a mesh orperforated plate with a desired opening size, for example, less thanabout 6.35 mm (¼ inch, 0.25 inch), (e.g., less than about 3.18 mm (⅛inch, 0.125 inch), less than about 1.59 mm ( 1/16 inch, 0.0625 inch), isless than about 0.79 mm ( 1/32 inch, 0.03125 inch), e.g., less thanabout 0.51 mm ( 1/50 inch, 0.02000 inch), less than about 0.40 mm ( 1/64inch, 0.015625 inch), less than about 0.23 mm (0.009 inch), less thanabout 0.20 mm ( 1/128 inch, 0.0078125 inch), less than about 0.18 mm(0.007 inch), less than about 0.13 mm (0.005 inch), or even less thanabout 0.10 mm ( 1/256 inch, 0.00390625 inch)). In one configuration thedesired biomass falls through the perforations or screen and thusbiomass larger than the perforations or screen are not irradiated. Theselarger materials can be re-processed, for example by comminuting, orthey can simply be removed from processing. In another configurationmaterial that is larger than the perforations is irradiated and thesmaller material is removed by the screening process or recycled. Inthis kind of a configuration, the conveyor itself (for example a part ofthe conveyor) can be perforated or made with a mesh. For example, in oneparticular embodiment the biomass material may be wet and theperforations or mesh allow water to drain away from the biomass beforeirradiation.

Screening of material can also be by a manual method, for example by anoperator or mechanoid (e.g., a robot equipped with a color, reflectivityor other sensor) that removes unwanted material. Screening can also beby magnetic screening wherein a magnet is disposed near the conveyedmaterial and the magnetic material is removed magnetically.

Optional pre-treatment processing can include heating the material. Forexample a portion of the conveyor can be sent through a heated zone. Theheated zone can be created, for example, by IR radiation, microwaves,combustion (e.g., gas, coal, oil, biomass), resistive heating and/orinductive coils. The heat can be applied from at least one side or morethan one side, can be continuous or periodic and can be for only aportion of the material or all the material. For example, a portion ofthe conveying trough can be heated by use of a heating jacket. Heatingcan be, for example, for the purpose of drying the material. In the caseof drying the material, this can also be facilitated, with or withoutheating, by the movement of a gas (e.g., air, oxygen, nitrogen, He, CO2,Argon) over and/or through the biomass as it is being conveyed.

Optionally, pre-treatment processing can include cooling the material.Cooling material is described in U.S. Pat. No. 7,900,857 to Medoff, thedisclosure of which in incorporated herein by reference. For example,cooling can be by supplying a cooling fluid, for example water (e.g.,with glycerol), or nitrogen (e.g., liquid nitrogen) to the bottom of theconveying trough. Alternatively, a cooling gas, for example, chillednitrogen can be blown over the biomass materials or under the conveyingsystem.

Another optional pre-treatment processing method can include adding amaterial to the biomass. The additional material can be added by, forexample, by showering, sprinkling and or pouring the material onto thebiomass as it is conveyed. Materials that can be added include, forexample, metals, ceramics and/or ions as described in U.S. Pat. App.Pub. 2010/0105119 A1 (filed Oct. 26, 2009) and U.S. Pat. App. Pub.2010/0159569 A1 (filed Dec. 16, 2009), the entire disclosures of whichare incorporated herein by reference. Optional materials that can beadded include acids and bases. Other materials that can be added areoxidants (e.g., peroxides, chlorates), polymers, polymerizable monomers(e.g., containing unsaturated bonds), water, catalysts, enzymes and/ororganisms. Materials can be added, for example, in pure form, as asolution in a solvent (e.g., water or an organic solvent) and/or as asolution. In some cases the solvent is volatile and can be made toevaporate e.g., by heating and/or blowing gas as previously described.The added material may form a uniform coating on the biomass or be ahomogeneous mixture of different components (e.g., biomass andadditional material). The added material can modulate the subsequentirradiation step by increasing the efficiency of the irradiation,damping the irradiation or changing the effect of the irradiation (e.g.,from electron beams to X-rays or heat). The method may have no impact onthe irradiation but may be useful for further downstream processing. Theadded material may help in conveying the material, for example, bylowering dust levels.

Biomass can be delivered to the conveyor (e.g., the vibratory conveyorsused in the vaults herein described) by a belt conveyor, a pneumaticconveyor, a screw conveyor, a hopper, a pipe, manually or by acombination of these. The biomass can, for example, be dropped, pouredand/or placed onto the conveyor by any of these methods. In someembodiments the material is delivered to the conveyor using an enclosedmaterial distribution system to help maintain a low oxygen atmosphereand/or control dust and fines. Lofted or air suspended biomass fines anddust are undesirable because these can form an explosion hazard ordamage the window foils of an electron gun (if such a device is used fortreating the material).

The material can be leveled to form a uniform thickness between about0.0312 and 5 inches (e.g., between about 0.0625 and 2.000 inches,between about 0.125 and 1 inches, between about 0.125 and 0.5 inches,between about 0.3 and 0.9 inches, between about 0.2 and 0.5 inchesbetween about 0.25 and 1.0 inches, between about 0.25 and 0.5 inches.

Generally, it is preferred to convey the material as quickly as possiblethrough the electron beam to maximize throughput. For example thematerial can be conveyed at rates of at least 1 ft./min, e.g., at least2 ft./min, at least 3 ft./min, at least 4 ft./min, at least 5 ft./min,at least 10 ft./min, at least 15 ft./min, 20, 25, 30, 35, 40, 45, 50ft./min. The rate of conveying is related to the beam current, forexample, for a ¼ inch thick biomass and 100 mA, the conveyor can move atabout 20 ft./min to provide a useful irradiation dosage, at 50 mA theconveyor can move at about 10 ft./min to provide approximately the sameirradiation dosage.

After the biomass material has been conveyed through the radiation zone,optional post-treatment processing can be done. The optionalpost-treatment processing can, for example, be a process described withrespect to the pre-irradiation processing. For example, the biomass canbe screened, heated, cooled, and/or combined with additives. Uniquely topost-irradiation, quenching of the radicals can occur, for example,quenching of radicals by the addition of fluids or gases (e.g., oxygen,nitrous oxide, ammonia, liquids), using pressure, heat, and/or theaddition of radical scavengers. For example, the biomass can be conveyedout of the enclosed conveyor and exposed to a gas (e.g., oxygen) whereit is quenched, forming carboxylated groups. In one embodiment thebiomass is exposed during irradiation to the reactive gas or fluid.Quenching of biomass that has been irradiated is described in U.S. Pat.No. 8,083,906 to Medoff, the entire disclosure of which is incorporateherein by reference.

If desired, one or more mechanical treatments can be used in addition toirradiation to further reduce the recalcitrance of thecarbohydrate-containing material. These processes can be applied before,during and or after irradiation.

In some cases, the mechanical treatment may include an initialpreparation of the feedstock as received, e.g., size reduction ofmaterials, such as by comminution, e.g., cutting, grinding, shearing,pulverizing or chopping. For example, in some cases, loose feedstock(e.g., recycled paper, starchy materials, or switchgrass) is prepared byshearing or shredding. Mechanical treatment may reduce the bulk densityof the carbohydrate-containing material, increase the surface area ofthe carbohydrate-containing material and/or decrease one or moredimensions of the carbohydrate-containing material.

Alternatively, or in addition, the feedstock material can be treatedwith another treatment, for example chemical treatments, such as with anacid (HCl, H₂SO₄, H₃PO₄), a base (e.g., KOH and NaOH), a chemicaloxidant (e.g., peroxides, chlorates, ozone), irradiation, steamexplosion, pyrolysis, sonication, oxidation, chemical treatment. Thetreatments can be in any order and in any sequence and combinations. Forexample, the feedstock material can first be physically treated by oneor more treatment methods, e.g., chemical treatment including and incombination with acid hydrolysis (e.g., utilizing HCl, H₂SO₄, H₃PO₄),radiation, sonication, oxidation, pyrolysis or steam explosion, and thenmechanically treated. This sequence can be advantageous since materialstreated by one or more of the other treatments, e.g., irradiation orpyrolysis, tend to be more brittle and, therefore, it may be easier tofurther change the structure of the material by mechanical treatment. Asanother example, a feedstock material can be conveyed through ionizingradiation using a conveyor as described herein and then mechanicallytreated. Chemical treatment can remove some or all of the lignin (forexample chemical pulping) and can partially or completely hydrolyze thematerial. The methods also can be used with pre-hydrolyzed material. Themethods also can be used with material that has not been pre hydrolyzedThe methods can be used with mixtures of hydrolyzed and non-hydrolyzedmaterials, for example with about 50% or more non-hydrolyzed material,with about 60% or more non-hydrolyzed material, with about 70% or morenon-hydrolyzed material, with about 80% or more non-hydrolyzed materialor even with 90% or more non-hydrolyzed material.

In addition to size reduction, which can be performed initially and/orlater in processing, mechanical treatment can also be advantageous for“opening up,” “stressing,” breaking or shattering thecarbohydrate-containing materials, making the cellulose of the materialsmore susceptible to chain scission and/or disruption of crystallinestructure during the physical treatment.

Methods of mechanically treating the carbohydrate-containing materialinclude, for example, milling or grinding. Milling may be performedusing, for example, a hammer mill, ball mill, colloid mill, conical orcone mill, disk mill, edge mill, Wiley mill, grist mill or other mill.Grinding may be performed using, for example, a cutting/impact typegrinder. Some exemplary grinders include stone grinders, pin grinders,coffee grinders, and burr grinders. Grinding or milling may be provided,for example, by a reciprocating pin or other element, as is the case ina pin mill. Other mechanical treatment methods include mechanicalripping or tearing, other methods that apply pressure to the fibers, andair attrition milling. Suitable mechanical treatments further includeany other technique that continues the disruption of the internalstructure of the material that was initiated by the previous processingsteps.

Mechanical feed preparation systems can be configured to produce streamswith specific characteristics such as, for example, specific maximumsizes, specific length-to-width, or specific surface areas ratios.Physical preparation can increase the rate of reactions, improve themovement of material on a conveyor, improve the irradiation profile ofthe material, improve the radiation uniformity of the material, orreduce the processing time required by opening up the materials andmaking them more accessible to processes and/or reagents, such asreagents in a solution.

The bulk density of feedstocks can be controlled (e.g., increased). Insome situations, it can be desirable to prepare a low bulk densitymaterial, e.g., by densifying the material (e.g., densification can makeit easier and less costly to transport to another site) and thenreverting the material to a lower bulk density state (e.g., aftertransport). The material can be densified, for example from less thanabout 0.2 g/cc to more than about 0.9 g/cc (e.g., less than about 0.3 tomore than about 0.5 g/cc, less than about 0.3 to more than about 0.9g/cc, less than about 0.5 to more than about 0.9 g/cc, less than about0.3 to more than about 0.8 g/cc, less than about 0.2 to more than about0.5 g/cc). For example, the material can be densified by the methods andequipment disclosed in U.S. Pat. No. 7,932,065 to Medoff andInternational Publication No. WO 2008/073186 (which was filed Oct. 26,2007, was published in English, and which designated the United States),the full disclosures of which are incorporated herein by reference.Densified materials can be processed by any of the methods describedherein, or any material processed by any of the methods described hereincan be subsequently densified.

In some embodiments, the material to be processed is in the form of afibrous material that includes fibers provided by shearing a fibersource. For example, the shearing can be performed with a rotary knifecutter.

For example, a fiber source, e.g., that is recalcitrant or that has hadits recalcitrance level reduced, can be sheared, e.g., in a rotary knifecutter, to provide a first fibrous material. The first fibrous materialis passed through a first screen, e.g., having an average opening sizeof 1.59 mm or less ( 1/16 inch, 0.0625 inch), provide a second fibrousmaterial. If desired, the fiber source can be cut prior to the shearing,e.g., with a shredder. For example, when a paper is used as the fibersource, the paper can be first cut into strips that are, e.g., ¼- to½-inch wide, using a shredder, e.g., a counter-rotating screw shredder,such as those manufactured by Munson (Utica, N.Y.). As an alternative toshredding, the paper can be reduced in size by cutting to a desired sizeusing a guillotine cutter. For example, the guillotine cutter can beused to cut the paper into sheets that are, e.g., 10 inches wide by 12inches long.

In some embodiments, the shearing of the fiber source and the passing ofthe resulting first fibrous material through a first screen areperformed concurrently. The shearing and the passing can also beperformed in a batch-type process.

For example, a rotary knife cutter can be used to concurrently shear thefiber source and screen the first fibrous material. A rotary knifecutter includes a hopper that can be loaded with a shredded fiber sourceprepared by shredding a fiber source.

In some implementations, the feedstock is physically treated prior tosaccharification and/or fermentation. Physical treatment processes caninclude one or more of any of those described herein, such as mechanicaltreatment, chemical treatment, irradiation, sonication, oxidation,pyrolysis or steam explosion. Treatment methods can be used incombinations of two, three, four, or even all of these technologies (inany order). When more than one treatment method is used, the methods canbe applied at the same time or at different times. Other processes thatchange a molecular structure of a biomass feedstock may also be used,alone or in combination with the processes disclosed herein.

Mechanical treatments that may be used, and the characteristics of themechanically treated carbohydrate-containing materials, are described infurther detail in U.S. Pat. App. Pub. 2012/0100577 A1, filed Oct. 18,2011, the full disclosure of which is hereby incorporated herein byreference.

Sonication, Pyrolysis, Oxidation, Steam Explosion

If desired, one or more sonication, pyrolysis, oxidative, or steamexplosion processes can be used instead of or in addition to irradiationto reduce or further reduce the recalcitrance of thecarbohydrate-containing material. For example, these processes can beapplied before, during and or after irradiation. These processes aredescribed in detail in U.S. Pat. No. 7,932,065 to Medoff, the fulldisclosure of which is incorporated herein by reference.

Use of Treated Biomass Material

Using the methods described herein, a starting biomass material (e.g.,plant biomass, animal biomass, paper, and municipal waste biomass) canbe used as feedstock to produce useful intermediates and products suchas organic acids, salts of organic acids, anhydrides, esters of organicacids and fuels, e.g., fuels for internal combustion engines orfeedstocks for fuel cells. Systems and processes are described hereinthat can use as feedstock cellulosic and/or lignocellulosic materialsthat are readily available, but often can be difficult to process, e.g.,municipal waste streams and waste paper streams, such as streams thatinclude newspaper, kraft paper, corrugated paper or mixtures of these.

In order to convert the feedstock to a form that can be readilyprocessed, the glucan- or xylan-containing cellulose in the feedstockcan be hydrolyzed to low molecular weight carbohydrates, such as sugars,by a saccharifying agent, e.g., an enzyme or acid, a process referred toas saccharification. The low molecular weight carbohydrates can then beused, for example, in an existing manufacturing plant, such as a singlecell protein plant, an enzyme manufacturing plant, or a fuel plant,e.g., an ethanol manufacturing facility.

The feedstock can be hydrolyzed using an enzyme, e.g., by combining thematerials and the enzyme in a solvent, e.g., in an aqueous solution.

Alternatively, the enzymes can be supplied by organisms that break downbiomass, such as the cellulose and/or the lignin portions of thebiomass, contain or manufacture various cellulolytic enzymes(cellulases), ligninases or various small molecule biomass-degradingmetabolites. These enzymes may be a complex of enzymes that actsynergistically to degrade crystalline cellulose or the lignin portionsof biomass. Examples of cellulolytic enzymes include: endoglucanases,cellobiohydrolases, and cellobiases (beta-glucosidases).

During saccharification a cellulosic substrate can be initiallyhydrolyzed by endoglucanases at random locations producing oligomericintermediates. These intermediates are then substrates for exo-splittingglucanases such as cellobiohydrolase to produce cellobiose from the endsof the cellulose polymer. Cellobiose is a water-soluble 1,4-linked dimerof glucose. Finally, cellobiase cleaves cellobiose to yield glucose. Theefficiency (e.g., time to hydrolyze and/or completeness of hydrolysis)of this process depends on the recalcitrance of the cellulosic material.

Intermediates and Products

Using the processes described herein, the biomass material can beconverted to one or more products, such as energy, fuels, foods andmaterials. Specific examples of products include, but are not limitedto, hydrogen, sugars (e.g., glucose, xylose, arabinose, mannose,galactose, fructose, disaccharides, oligosaccharides andpolysaccharides), alcohols (e.g., monohydric alcohols or dihydricalcohols, such as ethanol, n-propanol, isobutanol, sec-butanol,tert-butanol or n-butanol), hydrated or hydrous alcohols (e.g.,containing greater than 10%, 20%, 30% or even greater than 40% water),biodiesel, organic acids, hydrocarbons (e.g., methane, ethane, propane,isobutene, pentane, n-hexane, biodiesel, bio-gasoline and mixturesthereof), co-products (e.g., proteins, such as cellulolytic proteins(enzymes) or single cell proteins), and mixtures of any of these in anycombination or relative concentration, and optionally in combinationwith any additives (e.g., fuel additives). Other examples includecarboxylic acids, salts of a carboxylic acid, a mixture of carboxylicacids and salts of carboxylic acids and esters of carboxylic acids(e.g., methyl, ethyl and n-propyl esters), ketones (e.g., acetone),aldehydes (e.g., acetaldehyde), alpha and beta unsaturated acids (e.g.,acrylic acid) and olefins (e.g., ethylene). Other alcohols and alcoholderivatives include propanol, propylene glycol, 1,4-butanediol,1,3-propanediol, sugar alcohols (e.g., erythritol, glycol, glycerol,sorbitol threitol, arabitol, ribitol, mannitol, dulcitol, fucitol,iditol, isomalt, maltitol, lactitol, xylitol and other polyols), andmethyl or ethyl esters of any of these alcohols. Other products includemethyl acrylate, methyl methacrylate, lactic acid, citric acid, formicacid, acetic acid, propionic acid, butyric acid, succinic acid, valericacid, caproic acid, 3-hydroxypropionic acid, palmitic acid, stearicacid, oxalic acid, malonic acid, glutaric acid, oleic acid, linoleicacid, glycolic acid, gamma-hydroxybutyric acid, and mixtures thereof,salts of any of these acids, mixtures of any of the acids and theirrespective salts.

Any combination of the above products with each other, and/or of theabove products with other products, which other products may be made bythe processes described herein or otherwise, may be packaged togetherand sold as products. The products may be combined, e.g., mixed, blendedor co-dissolved, or may simply be packaged or sold together.

Any of the products or combinations of products described herein may besanitized or sterilized prior to selling the products, e.g., afterpurification or isolation or even after packaging, to neutralize one ormore potentially undesirable contaminants that could be present in theproduct(s). Such sanitation can be done with electron bombardment, forexample, be at a dosage of less than about 20 Mrad, e.g., from about 0.1to 15 Mrad, from about 0.5 to 7 Mrad, or from about 1 to 3 Mrad.

The processes described herein can produce various by-product streamsuseful for generating steam and electricity to be used in other parts ofthe plant (co-generation) or sold on the open market. For example, steamgenerated from burning by-product streams can be used in a distillationprocess. As another example, electricity generated from burningby-product streams can be used to power electron beam generators used inpretreatment.

The by-products used to generate steam and electricity are derived froma number of sources throughout the process. For example, anaerobicdigestion of wastewater can produce a biogas high in methane and a smallamount of waste biomass (sludge). As another example,post-saccharification and/or post-distillate solids (e.g., unconvertedlignin, cellulose, and hemicellulose remaining from the pretreatment andprimary processes) can be used, e.g., burned, as a fuel.

Other intermediates and products, including food and pharmaceuticalproducts, are described in U.S. Pat. App. Pub. 2010/0124583 A1,published May 20, 2010, to Medoff, the full disclosure of which ishereby incorporated by reference herein.

Lignin Derived Products

The spent biomass (e.g., spent lignocellulosic material) fromlignocellulosic processing by the methods described are expected to havea high lignin content and in addition to being useful for producingenergy through combustion in a Co-Generation plant, may have uses asother valuable products. For example, the lignin can be used as capturedas a plastic, or it can be synthetically upgraded to other plastics. Insome instances, it can also be converted to lignosulfonates, which canbe utilized as binders, dispersants, emulsifiers or as sequestrants.

When used as a binder, the lignin or a lignosulfonate can, e.g., beutilized in coal briquettes, in ceramics, for binding carbon black, forbinding fertilizers and herbicides, as a dust suppressant, in the makingof plywood and particle board, for binding animal feeds, as a binder forfiberglass, as a binder in linoleum paste and as a soil stabilizer.

As a dispersant, the lignin or lignosulfonates can be used, e.g.,concrete mixes, clay and ceramics, dyes and pigments, leather tanningand in gypsum board.

As an emulsifier, the lignin or lignosulfonates can be used, e.g., inasphalt, pigments and dyes, pesticides and wax emulsions.

As a sequestrant, the lignin or lignosulfonates can be used, e.g., inmicro-nutrient systems, cleaning compounds and water treatment systems,e.g., for boiler and cooling systems.

For energy production lignin generally has a higher energy content thanholocellulose (cellulose and hemicellulose) since it contains morecarbon than holocellulose. For example, dry lignin can have an energycontent of between about 11,000 and 12,500 BTU per pound, compared to7,000 an 8,000 BTU per pound of holocellulose. As such, lignin can bedensified and converted into briquettes and pellets for burning. Forexample, the lignin can be converted into pellets by any methoddescribed herein. For a slower burning pellet or briquette, the lignincan be crosslinked, such as applying a radiation dose of between about0.5 Mrad and 5 Mrad. Crosslinking can make a slower burning form factor.The form factor, such as a pellet or briquette, can be converted to a“synthetic coal” or charcoal by pyrolyzing in the absence of air, e.g.,at between 400 and 950° C. Prior to pyrolyzing, it can be desirable tocrosslink the lignin to maintain structural integrity.

Co-generation using spent biomass is described in U.S. ProvisionalApplication No. 61/774,773 the entire disclosure therein is hereinincorporated by reference.

Biomass Processing after Irradiation

After irradiation the biomass may be transferred to a vessel forsaccharification. Alternately, the biomass can be heated after thebiomass is irradiated prior to the saccharification step. The biomasscan be, for example, by IR radiation, microwaves, combustion (e.g., gas,coal, oil, biomass), resistive heating and/or inductive coils. Thisheating can be in a liquid, for example, in water or other water-basedsolvents. The heat can be applied from at least one side or more thanone side, can be continuous or periodic and can be for only a portion ofthe material or all the material. The biomass may be heated totemperatures above 90° C. in an aqueous liquid that may have an acid ora base present. For example, the aqueous biomass slurry may be heated to90 to 150° C., alternatively, 105 to 145° C., optionally 110 to 140° C.or further optionally from 115 to 135° C. The time that the aqueousbiomass mixture is held at the peak temperature is 1 to 12 hours,alternately, 1 to 6 hours, optionally 1 to 4 hours at the peaktemperature. In some instances, the aqueous biomass mixture is acidic,and the pH is between 1 and 5, optionally 1 to 4, or alternately, 2 to3. In other instances, the aqueous biomass mixture is alkaline and thepH is between 6 and 13, alternately, 8 to 12, or optionally, 8 to 11.

Saccharification

The treated biomass materials can be saccharified, generally bycombining the material and a cellulase enzyme in a fluid medium, e.g.,an aqueous solution. In some cases, the material is boiled, steeped, orcooked in hot water prior to saccharification, as described in U.S. Pat.App. Pub. 2012/0100577 A1 by Medoff and Masterman, published on Apr. 26,2012, the entire contents of which are incorporated herein.

The saccharification process can be partially or completely performed ina tank (e.g., a tank having a volume of at least 4000, 40,000, or500,000 L) in a manufacturing plant, and/or can be partially orcompletely performed in transit, e.g., in a rail car, tanker truck, orin a supertanker or the hold of a ship. The time required for completesaccharification will depend on the process conditions and thecarbohydrate-containing material and enzyme used. If saccharification isperformed in a manufacturing plant under controlled conditions, thecellulose may be substantially entirely converted to sugar, e.g.,glucose in about 12-96 hours. If saccharification is performed partiallyor completely in transit, saccharification may take longer.

It is generally preferred that the tank contents be mixed duringsaccharification, e.g., using jet mixing as described in InternationalApp. No. PCT/US2010/035331, filed May 18, 2010, which was published inEnglish as WO 2010/135380 and designated the United States, the fulldisclosure of which is incorporated by reference herein.

The addition of surfactants can enhance the rate of saccharification.Examples of surfactants include non-ionic surfactants, such as a Tween®20 or Tween® 80 polyethylene glycol surfactants, ionic surfactants, oramphoteric surfactants.

It is generally preferred that the concentration of the sugar solutionresulting from saccharification be relatively high, e.g., greater than40%, or greater than 50, 60, 70, 80, 90 or even greater than 95% byweight. Water may be removed, e.g., by evaporation, to increase theconcentration of the sugar solution. This reduces the volume to beshipped, and also inhibits microbial growth in the solution.

Alternatively, sugar solutions of lower concentrations may be used, inwhich case it may be desirable to add an antimicrobial additive, e.g., abroad spectrum antibiotic, in a low concentration, e.g., 50 to 150 ppm.Other suitable antibiotics include amphotericin B, ampicillin,chloramphenicol, ciprofloxacin, gentamicin, hygromycin B, kanamycin,neomycin, penicillin, puromycin, streptomycin. Antibiotics will inhibitgrowth of microorganisms during transport and storage, and can be usedat appropriate concentrations, e.g., between 15 and 1000 ppm by weight,e.g., between 25 and 500 ppm, or between 50 and 150 ppm. If desired, anantibiotic can be included even if the sugar concentration is relativelyhigh. Alternatively, other additives with anti-microbial of preservativeproperties may be used. Preferably the antimicrobial additive(s) arefood-grade.

A relatively high concentration solution can be obtained by limiting theamount of water added to the carbohydrate-containing material with theenzyme. The concentration can be controlled, e.g., by controlling howmuch saccharification takes place. For example, concentration can beincreased by adding more carbohydrate-containing material to thesolution. In order to keep the sugar that is being produced in solution,a surfactant can be added, e.g., one of those discussed above.Solubility can also be increased by increasing the temperature of thesolution. For example, the solution can be maintained at a temperatureof 40-50° C., 60-80° C., or even higher.

Saccharifying Agents

Suitable cellulolytic enzymes include cellulases from species in thegenera Bacillus, Coprinus, Myceliophthora, Cephalosporium, Scytalidium,Penicillium, Aspergillus, Pseudomonas, Humicola, Fusarium, Thielavia,Acremonium, Chrysosporium and Trichoderma, especially those produced bya strain selected from the species Aspergillus (see, e.g., EP Pub. No. 0458 162), Humicola insolens (reclassified as Scytalidium thermophilum,see, e.g., U.S. Pat. No. 4,435,307), Coprinus cinereus, Fusariumoxysporum, Myceliophthora thermophila, Meripilus giganteus, Thielaviaterrestris, Acremonium sp. (including, but not limited to, A.persicinum, A. acremonium, A. brachypenium, A. dichromosporum, A.obclavatum, A. pinkertoniae, A. roseogriseum, A. incoloratum, and A.furatum). Preferred strains include Humicola insolens DSM 1800, Fusariumoxysporum DSM 2672, Myceliophthora thermophila CBS 117.65,Cephalosporium sp. RYM-202, Acremonium sp. CBS 478.94, Acremonium sp.CBS 265.95, Acremonium persicinum CBS 169.65, Acremonium acremonium AHU9519, Cephalosporium sp. CBS 535.71, Acremonium brachypenium CBS 866.73,Acremonium dichromosporum CBS 683.73, Acremonium obclavatum CBS 311.74,Acremonium pinkertoniae CBS 157.70, Acremonium roseogriseum CBS 134.56,Acremonium incoloratum CBS 146.62, and Acremonium furatum CBS 299.70H.Cellulolytic enzymes may also be obtained from Chrysosporium, preferablya strain of Chrysosporium lucknowense. Additional strains that can beused include, but are not limited to, Trichoderma (particularly T.viride, T reesei, and T. koningii), alkalophilic Bacillus (see, forexample, U.S. Pat. No. 3,844,890 and EP Pub. No. 0 458 162), andStreptomyces (see, e.g., EP Pub. No. 0 458 162).

In addition to or in combination to enzymes, acids, bases and otherchemicals (e.g., oxidants) can be utilized to saccharify lignocellulosicand cellulosic materials. These can be used in any combination orsequence (e.g., before, after and/or during addition of an enzyme). Forexample strong mineral acids can be utilized (e.g. HCl, H₂SO₄, H₃PO₄)and strong bases (e.g., NaOH, KOH).

Sugars

In the processes described herein, for example after saccharification,sugars (e.g., glucose and xylose) can be isolated. For example sugarscan be isolated by precipitation, crystallization, chromatography (e.g.,simulated moving bed chromatography, high pressure chromatography),centrifugation, extraction, any other isolation method known in the art,and combinations thereof.

Hydrogenation and Other Chemical Transformations

The processes described herein can include hydrogenation. For exampleglucose and xylose can be hydrogenated to sorbitol and xylitolrespectively. Hydrogenation can be accomplished by use of a catalyst(e.g., Pt/gamma-Al₂O₃, Ru/C, Raney Nickel, or other catalysts know inthe art) in combination with H₂ under high pressure (e.g., 10 to 12000psi). Other types of chemical transformation of the products from theprocesses described herein can be used, for example production oforganic sugar derived products such (e.g., furfural and furfural-derivedproducts). Chemical transformations of sugar derived products aredescribed in U.S. application Ser. No. 13/934,704, filed Jul. 3, 2013,the disclosure of which is incorporated herein by reference in itsentirety.

Fermentation

Yeast and Zymomonas bacteria, for example, can be used for fermentationor conversion of sugar(s) to alcohol(s). Other microorganisms arediscussed below. The optimum pH for fermentations is about pH 4 to 7.For example, the optimum pH for yeast is from about pH 4 to 5, while theoptimum pH for Zymomonas is from about pH 5 to 6. Typical fermentationtimes are about 24 to 168 hours (e.g., 24 to 96 hrs.) with temperaturesin the range of 20° C. to 40° C. (e.g., 26° C. to 40° C.), howeverthermophilic microorganisms prefer higher temperatures.

In some embodiments, e.g., when anaerobic organisms are used, at least aportion of the fermentation is conducted in the absence of oxygen, e.g.,under a blanket of an inert gas such as N2, Ar, He, CO2 or mixturesthereof. Additionally, the mixture may have a constant purge of an inertgas flowing through the tank during part of or all of the fermentation.In some cases, anaerobic condition, can be achieved or maintained bycarbon dioxide production during the fermentation and no additionalinert gas is needed.

In some embodiments, all or a portion of the fermentation process can beinterrupted before the low molecular weight sugar is completelyconverted to a product (e.g., ethanol). The intermediate fermentationproducts include sugar and carbohydrates in high concentrations. Thesugars and carbohydrates can be isolated via any means known in the art.These intermediate fermentation products can be used in preparation offood for human or animal consumption. Additionally or alternatively, theintermediate fermentation products can be ground to a fine particle sizein a stainless-steel laboratory mill to produce a flour-like substance.Jet mixing may be used during fermentation, and in some casessaccharification and fermentation are performed in the same tank.

Nutrients for the microorganisms may be added during saccharificationand/or fermentation, for example the food-based nutrient packagesdescribed in U.S. Pat. App. Pub. 2012/0052536, filed Jul. 15, 2011, thecomplete disclosure of which is incorporated herein by reference.

“Fermentation” includes the methods and products that are disclosed inWO 2013/096700, filed Dec. 22, 2012, and U.S. App. No.PCT/US2012/071083, filed Dec. 22, 2012, the contents of both of whichare incorporated by reference herein in their entirety.

Mobile fermenters can be utilized, as described in International App.No. PCT/US2007/074028 (which was filed Jul. 20, 2007, was published inEnglish as WO 2008/011598 and designated the United States) and has a USissued U.S. Pat. No. 8,318,453, the contents of which are incorporatedherein in its entirety. Similarly, the saccharification equipment can bemobile. Further, saccharification and/or fermentation may be performedin part or entirely during transit.

Fermentation Agents

The microorganism(s) used in fermentation can be naturally-occurringmicroorganisms and/or engineered microorganisms. For example, themicroorganism can be a bacterium (including, but not limited to, e.g., acellulolytic bacterium), a fungus, (including, but not limited to, e.g.,a yeast), a plant, a protist, e.g., a protozoa or a fungus-like protest(including, but not limited to, e.g., a slime mold), or an alga. Whenthe organisms are compatible, mixtures of organisms can be utilized.

Suitable fermenting microorganisms have the ability to convertcarbohydrates, such as glucose, fructose, xylose, arabinose, mannose,galactose, oligosaccharides or polysaccharides into fermentationproducts. Fermenting microorganisms include strains of the genusSaccharomyces spp. (including, but not limited to, S. cerevisiae(baker's yeast), S. distaticus, S. uvarum), the genus Kluyveromyces,(including, but not limited to, K. marxianus, K. fragilis), the genusCandida (including, but not limited to, C. pseudotropicalis, and C.brassicae), Pichia stipitis (a relative of Candida shehatae), the genusClavispora (including, but not limited to, C. lusitaniae and C.opuntiae), the genus Pachysolen (including, but not limited to, P.tannophilus), the genus Bretannomyces (including, but not limited to,e.g., B. clausenii (Philippidis, G. P., 1996, Cellulose bioconversiontechnology, in Handbook on Bioethanol: Production and Utilization,Wyman, C. E., ed., Taylor & Francis, Washington, D.C., 179-212)). Othersuitable microorganisms include, for example, Zymomonas mobilis,Clostridium spp. (including, but not limited to, C. thermocellum(Philippidis, 1996, supra), C. saccharobutylacetonicum, C. tyrobutyricumC. saccharobutylicum, C. Puniceum, C. beijernckii, and C.acetobutylicum), Moniliella spp. (including but not limited to M.pollinis, M. tomentosa, M. madida, M. nigrescens, M. oedocephali, M.megachiliensis), Yarrowia lipolytica, Aureobasidium sp.,Trichosporonoides sp., Trigonopsis variabilis, Trichosporon sp.,Moniliellaacetoabutans sp., Typhula variabilis, Candida magnoliae,Ustilaginomycetes sp., Pseudozyma tsukubaensis, yeast species of generaZygosaccharomyces, Debaryomyces, Hansenula and Pichia, and fungi of thedematioid genus Torula (e.g., T. corallina).

Many such microbial strains are publicly available, either commerciallyor through depositories such as the ATCC (American Type CultureCollection, Manassas, Va., USA), the NRRL (Agricultural Research ServiceCulture Collection, Peoria, Ill., USA), or the DSMZ (Deutsche Sammlungvon Mikroorganismen and Zellkulturen GmbH, Braunschweig, Germany), toname a few.

Commercially available yeasts include, for example, RED STAR®/LesaffreEthanol Red (available from Red Star/Lesaffre, USA), FALI® (availablefrom Fleischmann's Yeast, a division of Burns Philip Food Inc., USA),SUPERSTART® (Lallemand Biofuels and Distilled Spirits, Canada), EAGLE C6FUEL™ or C6 FUEL™ (available from Lallemand Biofuels and DistilledSpirits, Canada), GERT STRAND® (available from Gert Strand AB, Sweden)and FERMOL® (available from DSM Specialties).

Distillation

After fermentation, the resulting fluids can be distilled using, forexample, a “beer column” to separate ethanol and other alcohols from themajority of water and residual solids. The vapor exiting the beer columncan be, e.g., 35% by weight ethanol and can be fed to a rectificationcolumn. A mixture of nearly azeotropic (92.5%) ethanol and water fromthe rectification column can be purified to pure (99.5%) ethanol usingvapor-phase molecular sieves. The beer column bottoms can be sent to thefirst effect of a three-effect evaporator. The rectification columnreflux condenser can provide heat for this first effect. After the firsteffect, solids can be separated using a centrifuge and dried in a rotarydryer. A portion (25%) of the centrifuge effluent can be recycled tofermentation and the rest sent to the second and third evaporatoreffects. Most of the evaporator condensate can be returned to theprocess as fairly clean condensate with a small portion split off towaste water treatment to prevent build-up of low-boiling compounds.

Hydrocarbon-Containing Materials and Wood

In other embodiments utilizing the methods and systems described herein,hydrocarbon-containing materials can be processed. Any process describedherein can be used to treat any hydrocarbon-containing material hereindescribed. “Hydrocarbon-containing materials,” as used herein, is meantto include oil sands, oil shale, tar sands, coal dust, coal slurry,bitumen, various types of coal, and other naturally-occurring andsynthetic materials that include both hydrocarbon components and solidmatter. The solid matter can include wood, rock, sand, clay, stone,silt, drilling slurry, or other solid organic and/or inorganic matter.The term can also include waste products such as drilling waste andby-products, refining waste and by-products, or other waste productscontaining hydrocarbon components, such as asphalt shingling andcovering, asphalt pavement, etc.

In yet other embodiments utilizing the methods and systems describedherein, wood and wood containing produces can be processed. For examplelumber products can be processed, e.g., boards, sheets, laminates,beams, particle boards, composites, rough cut wood, soft wood and hardwood. In addition cut trees, bushes, wood chips sawdust, roots, bark,stumps, decomposed wood and other wood containing biomass material canbe processed.

Conveying Systems

Various conveying systems can be used to convey the biomass material,for example, to a vault and under an electron beam in a vault. Exemplaryconveyors are belt conveyors, pneumatic conveyors, screw conveyors,carts, trains, trains or carts on rails, elevators, front loaders,backhoes, cranes, various scrapers and shovels, trucks, and throwingdevices can be used. For example, vibratory conveyors can be used invarious processes described herein, for example, as disclosed in US.Provisional Application 61/711,801 filed Oct. 10, 2012, the entiredisclosure of which is herein incorporated by reference.

OTHER EMBODIMENTS

Any material, processes or processed materials discussed herein can beused to make products and/or intermediates such as composites, fillers,binders, plastic additives, adsorbents and controlled release agents.The methods can include densification, for example, by applying pressureand heat to the materials. For example composites can be made bycombining fibrous materials with a resin or polymer. For exampleradiation cross-linkable resin, e.g., a thermoplastic resin can becombined with a fibrous material to provide a fibrousmaterial/cross-linkable resin combination. Such materials can be, forexample, useful as building materials, protective sheets, containers andother structural materials (e.g., molded and/or extruded products).Absorbents can be, for example, in the form of pellets, chips, fibersand/or sheets. Adsorbents can be used, for example, as pet bedding,packaging material or in pollution control systems. Controlled releasematrices can also be the form of, for example, pellets, chips, fibersand or sheets. The controlled release matrices can, for example, be usedto release drugs, biocides, fragrances. For example, composites,absorbents and control release agents and their uses are described inU.S. Serial No. PCT/US2006/010648, filed Mar. 23, 2006, and U.S. Pat.No. 8,074,910 filed Nov. 22, 2011, the entire disclosures of which areherein incorporated by reference.

In some instances the biomass material is treated at a first level toreduce recalcitrance, e.g., utilizing accelerated electrons, toselectively release one or more sugars (e.g., xylose). The biomass canthen be treated to a second level to release one or more other sugars(e.g., glucose). Optionally, the biomass can be dried betweentreatments. The treatments can include applying chemical and biochemicaltreatments to release the sugars. For example, a biomass material can betreated to a level of less than about 20 Mrad (e.g., less than about 15Mrad, less than about 10 Mrad, less than about 5 Mrad, less than about 2Mrad) and then treated with a solution of sulfuric acid, containing lessthan 10% sulfuric acid (e.g., less than about 9%, less than about 8%,less than about 7%, less than about 6%, less than about 5%, less thanabout 4%, less than about 3%, less than about 2%, less than about 1%,less than about 0.75%, less than about 0.50%, less than about 0.25%) torelease xylose. Xylose, for example that is released into solution, canbe separated from solids and optionally the solids washed with asolvent/solution (e.g., with water and/or acidified water). Optionally,the solids can be dried, for example in air and/or under vacuumoptionally with heating (e.g., below about 150 deg C., below about 120deg C.) to a water content below about 25 wt. % (below about 20 wt. %,below about 15 wt. %, below about 10 wt. %, below about 5 wt. %). Thesolids can then be treated with a level of less than about 30 Mrad(e.g., less than about 25 Mrad, less than about 20 Mrad, less than about15 Mrad, less than about 10 Mrad, less than about 5 Mrad, less thanabout 1 Mrad or even not at all) and then treated with an enzyme (e.g.,a cellulase) to release glucose. The glucose (e.g., glucose in solution)can be separated from the remaining solids. The solids can then befurther processed, for example utilized to make energy or other products(e.g., lignin derived products).

Flavors, Fragrances and Colorants

Any of the products and/or intermediates described herein, for example,produced by the processes, systems and/or equipment described herein,can be combined with flavors, fragrances, colorants and/or mixtures ofthese. For example, any one or more of (optionally along with flavors,fragrances and/or colorants) sugars, organic acids, fuels, polyols, suchas sugar alcohols, biomass, fibers and composites can be combined with(e.g., formulated, mixed or reacted) or used to make other products. Forexample, one or more such product can be used to make soaps, detergents,candies, drinks (e.g., cola, wine, beer, liquors such as gin or vodka,sports drinks, coffees, teas), pharmaceuticals, adhesives, sheets (e.g.,woven, none woven, filters, tissues) and/or composites (e.g., boards).For example, one or more such product can be combined with herbs,flowers, petals, spices, vitamins, potpourri, or candles. For example,the formulated, mixed or reacted combinations can haveflavors/fragrances of grapefruit, orange, apple, raspberry, banana,lettuce, celery, cinnamon, chocolate, vanilla, peppermint, mint, onion,garlic, pepper, saffron, ginger, milk, wine, beer, tea, lean beef, fish,clams, olive oil, coconut fat, pork fat, butter fat, beef bouillon,legume, potatoes, marmalade, ham, coffee and cheeses.

Flavors, fragrances and colorants can be added in any amount, such asbetween about 0.001 wt. % to about 30 wt. %, e.g., between about 0.01 toabout 20, between about 0.05 to about 10, or between about 0.1 wt. % toabout 5 wt. %. These can be formulated, mixed and or reacted (e.g., withany one of more product or intermediate described herein) by any meansand in any order or sequence (e.g., agitated, mixed, emulsified, gelled,infused, heated, sonicated, and/or suspended). Fillers, binders,emulsifier, antioxidants can also be utilized, for example protein gels,starches and silica.

In one embodiment the flavors, fragrances and colorants can be added tothe biomass immediately after the biomass is irradiated such that thereactive sites created by the irradiation may react with reactivecompatible sites of the flavors, fragrances, and colorants.

The flavors, fragrances and colorants can be natural and/or syntheticmaterials. These materials can be one or more of a compound, acomposition or mixtures of these (e.g., a formulated or naturalcomposition of several compounds). Optionally the flavors, fragrances,antioxidants and colorants can be derived biologically, for example,from a fermentation process (e.g., fermentation of saccharifiedmaterials as described herein). Alternatively, or additionally theseflavors, fragrances and colorants can be harvested from a whole organism(e.g., plant, fungus, animal, bacteria or yeast) or a part of anorganism. The organism can be collected and or extracted to providecolor, flavors, fragrances and/or antioxidant by any means includingutilizing the methods, systems and equipment described herein, hot waterextraction, supercritical fluid extraction, chemical extraction (e.g.,solvent or reactive extraction including acids and bases), mechanicalextraction (e.g., pressing, comminuting, filtering), utilizing anenzyme, utilizing a bacteria such as to break down a starting material,and combinations of these methods. The compounds can be derived by achemical reaction, for example, the combination of a sugar (e.g., asproduced as described herein) with an amino acid (Maillard reaction).The flavor, fragrance, antioxidant and/or colorant can be anintermediate and or product produced by the methods, equipment orsystems described herein, for example and ester and a lignin derivedproduct.

Some examples of flavor, fragrances or colorants are polyphenols.Polyphenols are pigments responsible for the red, purple and bluecolorants of many fruits, vegetables, cereal grains, and flowers.Polyphenols also can have antioxidant properties and often have a bittertaste. The antioxidant properties make these important preservatives. Onclass of polyphenols are the flavonoids, such as Anthocyanidines,flavanonols, flavan-3-ols, s, flavanones and flavanonols. Other phenoliccompounds that can be used include phenolic acids and their esters, suchas chlorogenic acid and polymeric tannins.

Among the colorants inorganic compounds, minerals or organic compoundscan be used, for example titanium dioxide, zinc oxide, aluminum oxide,cadmium yellow (E.g., CdS), cadmium orange (e.g., CdS with some Se),alizarin crimson (e.g., synthetic or non-synthetic rose madder),ultramarine (e.g., synthetic ultramarine, natural ultramarine, syntheticultramarine violet), cobalt blue, cobalt yellow, cobalt green, viridian(e.g., hydrated chromium(III)oxide), chalcophylite, conichalcite,cornubite, cornwallite and liroconite. Black pigments such as carbonblack and self-dispersed blacks may be used.

Some flavors and fragrances that can be utilized include ACALEA TBHQ,ACET C-6, ALLYL AMYL GLYCOLATE, ALPHA TERPINEOL, AMBRETTOLIDE, AMBRINOL95, ANDRANE, APHERMATE, APPLELIDE, BACDANOL®, BERGAMAL, BETA IONONEEPDXIDE, BETA NAPHTHYL ISO-BUTYL ETHER, BICYCLONONALACTONE, BORNAFIX®,CANTHOXAL, CASHMERAN®, CASHMERAN® VELVET, CASSIFFIX®, CEDRAFIX,CEDRAMBER®, CEDRYL ACETATE, CELESTOLIDE, CINNAMALVA, CITRAL DIMETHYLACETATE, CITROLATE™, CITRONELLOL 700, CITRONELLOL 950, CITRONELLOLCOEUR, CITRONELLYL ACETATE, CITRONELLYL ACETATE PURE, CITRONELLYLFORMATE, CLARYCET, CLONAL, CONIFERAN, CONIFERAN PURE, CORTEX ALDEHYDE50% PEOMOSA, CYCLABUTE, CYCLACET®, CYCLAPROP®, CYCLEMAX™, CYCLOHEXYLETHYL ACETATE, DAMASCOL, DELTA DAMASCONE, DIHYDRO CYCLACET, DIHYDROMYRCENOL, DIHYDRO TERPINEOL, DIHYDRO TERPINYL ACETATE, DIMETHYLCYCLORMOL, DIMETHYL OCTANOL PQ, DIMYRCETOL, DIOLA, DIPENTENE, DULCINYL®RECRYSTALLIZED, ETHYL-3-PHENYL GLYCIDATE, FLEURAMONE, FLEURANIL, FLORALSUPER, FLORALOZONE, FLORIFFOL, FRAISTONE, FRUCTONE, GALAXOLIDE® 50,GALAXOLIDE® 50 BB, GALAXOLIDE® 50 IPM, GALAXOLIDE® UNDILUTED,GALBASCONE, GERALDEHYDE, GERANIOL 5020, GERANIOL 600 TYPE, GERANIOL 950,GERANIOL 980 (PURE), GERANIOL CFT COEUR, GERANIOL COEUR, GERANYL ACETATECOEUR, GERANYL ACETATE, PURE, GERANYL FORMATE, GRISALVA, GUAIYL ACETATE,HELIONAL™, HERBAC, HERBALIME™, HEXADECANOLIDE, HEXALON, HEXENYLSALICYLATE CIS 3-, HYACINTH BODY, HYACINTH BODY NO. 3, HYDRATROPICALDEHYDE. DMA, HYDROXYOL, INDOLAROME, INTRELEVEN ALDEHYDE, INTRELEVENALDEHYDE SPECIAL, IONONE ALPHA, IONONE BETA, ISO CYCLO CITRAL, ISO CYCLOGERANIOL, ISO E SUPER®, ISOBUTYL QUINOLINE, JASMAL, JESSEMAL®,KHARISMAL®, KHARISMAL® SUPER, KHUSINIL, KOAVONE®, KOHINOOL®, LIFFAROME™,LIMOXAL, LINDENOL™, LYRAL®, LYRAME SUPER, MANDARIN ALD 10% TM ETH, CITR,MARITIMA, MCK CHINESE, MEIJIFF™, MELAFLEUR, MELOZONE, METHYLANTHRANILATE, METHYL IONONE ALPHA EXTRA, METHYL IONONE GAMMA A, METHYLIONONE GAMMA COEUR, METHYL IONONE GAMMA PURE, METHYL LAVENDER KETONE,MONTAVERDI®, MUGUESIA, MUGUET ALDEHYDE 50, MUSK Z4, MYRAC ALDEHYDE,MYRCENYL ACETATE, NECTARATE™, NEROL 900, NERYL ACETATE, OCIMENE,OCTACETAL, ORANGE FLOWER ETHER, ORIVONE, ORRINIFF 25%, OXASPIRANE,OZOFLEUR, PAMPLEFLEUR®, PEOMOSA, PHENOXANOL®, PICONIA, PRECYCLEMONE B,PRENYL ACETATE, PRISMANTOL, RESEDA BODY, ROSALVA, ROSAMUSK, SANJINOL,SANTALIFF™, SYVERTAL, TERPINEOL, TERPINOLENE 20, TERPINOLENE 90 PQ,TERPINOLENE RECT., TERPINYL ACETATE, TERPINYL ACETATE JAX, TETRAHYDRO,MUGUOL®, TETRAHYDRO MYRCENOL, TETRAMERAN, TIMBERSILK™, TOBACAROL,TRIMOFIX® O TT, TRIPLAL®, TRISAMBER®, VANORIS, VERDOX™ VERDOX™ HC,VERTENEX®, VERTENEX® HC, VERTOFIX® COEUR, VERTOLIFF, VERTOLIFF ISO,VIOLIFF, VIVALDIE, ZENOLIDE, ABS INDIA 75 PCT MIGLYOL, ABS MOROCCO 50PCT DPG, ABS MOROCCO 50 PCT TEC, ABSOLUTE FRENCH, ABSOLUTE INDIA,ABSOLUTE MD 50 PCT BB, ABSOLUTE MOROCCO, CONCENTRATE PG, TINCTURE 20PCT, AMBERGRIS, AMBRETTE ABSOLUTE, AMBRETTE SEED OIL, ARMOISE OIL 70 PCTTHUYONE, BASIL ABSOLUTE GRAND VERT, BASIL GRAND VERT ABS MD, BASIL OILGRAND VERT, BASIL OIL VERVEINA, BASIL OIL VIETNAM, BAY OIL TERPENELESS,BEESWAX ABS N G, BEESWAX ABSOLUTE, BENZOIN RESINOID SIAM, BENZOINRESINOID SIAM 50 PCT DPG, BENZOIN RESINOID SIAM 50 PCT PG, BENZOINRESINOID SIAM 70.5 PCT TEC, BLACKCURRANT BUD ABS 65 PCT PG, BLACKCURRANTBUD ABS MD 37 PCT TEC, BLACKCURRANT BUD ABS MIGLYOL, BLACKCURRANT BUDABSOLUTE BURGUNDY, BOIS DE ROSE OIL, BRAN ABSOLUTE, BRAN RESINOID, BROOMABSOLUTE ITALY, CARDAMOM GUATEMALA CO2 EXTRACT, CARDAMOM OIL GUATEMALA,CARDAMOM OIL INDIA, CARROT HEART, CASSIE ABSOLUTE EGYPT, CASSIE ABSOLUTEMD 50 PCT IPM, CASTOREUM ABS 90 PCT TEC, CASTOREUM ABS C 50 PCT MIGLYOL,CASTOREUM ABSOLUTE, CASTOREUM RESINOID, CASTOREUM RESINOID 50 PCT DPG,CEDROL CEDRENE, CEDRUS ATLANTICA OIL REDIST, CHAMOMILE OIL ROMAN,CHAMOMILE OIL WILD, CHAMOMILE OIL WILD LOW LIMONENE, CINNAMON BARK OILCEYLAN, CISTE ABSOLUTE, CISTE ABSOLUTE COLORLESS, CITRONELLA OIL ASIAIRON FREE, CIVET ABS 75 PCT PG, CIVET ABSOLUTE, CIVET TINCTURE 10 PCT,CLARY SAGE ABS FRENCH DECOL, CLARY SAGE ABSOLUTE FRENCH, CLARY SAGEC'LESS 50 PCT PG, CLARY SAGE OIL FRENCH, COPAIBA BALSAM, COPAIBA BALSAMOIL, CORIANDER SEED OIL, CYPRESS OIL, CYPRESS OIL ORGANIC, DAVANA OIL,GALBANOL, GALBANUM ABSOLUTE COLORLESS, GALBANUM OIL, GALBANUM RESINOID,GALBANUM RESINOID 50 PCT DPG, GALBANUM RESINOID HERCOLYN BHT, GALBANUMRESINOID TEC BHT, GENTIANE ABSOLUTE MD 20 PCT BB, GENTIANE CONCRETE,GERANIUM ABS EGYPT MD, GERANIUM ABSOLUTE EGYPT, GERANIUM OIL CHINA,GERANIUM OIL EGYPT, GINGER OIL 624, GINGER OIL RECTIFIED SOLUBLE,GUAIACWOOD HEART, HAY ABS MD 50 PCT BB, HAY ABSOLUTE, HAY ABSOLUTE MD 50PCT TEC, HEALINGWOOD, HYSSOP OIL ORGANIC, IMMORTELLE ABS YUGO MD 50 PCTTEC, IMMORTELLE ABSOLUTE SPAIN, IMMORTELLE ABSOLUTE YUGO, JASMIN ABSINDIA MD, JASMIN ABSOLUTE EGYPT, JASMIN ABSOLUTE INDIA, ASMIN ABSOLUTEMOROCCO, JASMIN ABSOLUTE SAMBAC, JONQUILLE ABS MD 20 PCT BB, JONQUILLEABSOLUTE France, JUNIPER BERRY OIL FLG, JUNIPER BERRY OIL RECTIFIEDSOLUBLE, LABDANUM RESINOID 50 PCT TEC, LABDANUM RESINOID BB, LABDANUMRESINOID MD, LABDANUM RESINOID MD 50 PCT BB, LAVANDIN ABSOLUTE H,LAVANDIN ABSOLUTE MD, LAVANDIN OIL ABRIAL ORGANIC, LAVANDIN OIL GROSSOORGANIC, LAVANDIN OIL SUPER, LAVENDER ABSOLUTE H, LAVENDER ABSOLUTE MD,LAVENDER OIL COUMARIN FREE, LAVENDER OIL COUMARIN FREE ORGANIC, LAVENDEROIL MAILLETTE ORGANIC, LAVENDER OIL MT, MACE ABSOLUTE BB, MAGNOLIAFLOWER OIL LOW METHYL EUGENOL, MAGNOLIA FLOWER OIL, MAGNOLIA FLOWER OILMD, MAGNOLIA LEAF OIL, MANDARIN OIL MD, MANDARIN OIL MD BHT, MATEABSOLUTE BB, MOSS TREE ABSOLUTE MD TEX IFRA 43, MOSS-OAK ABS MD TEC IFRA43, MOSS-OAK ABSOLUTE IFRA 43, MOSS-TREE ABSOLUTE MD IPM IFRA 43, MYRRHRESINOID BB, MYRRH RESINOID MD, MYRRH RESINOID TEC, MYRTLE OIL IRONFREE, MYRTLE OIL TUNISIA RECTIFIED, NARCISSE ABS MD 20 PCT BB, NARCISSEABSOLUTE FRENCH, NEROLI OIL TUNISIA, NUTMEG OIL TERPENELESS, OEILLETABSOLUTE, OLIBANUM RESINOID, OLIBANUM RESINOID BB, OLIBANUM RESINOIDDPG, OLIBANUM RESINOID EXTRA 50 PCT DPG, OLIBANUM RESINOID MD, OLIBANUMRESINOID MD 50 PCT DPG, OLIBANUM RESINOID TEC, OPOPONAX RESINOID TEC,ORANGE BIGARADE OIL MD BHT, ORANGE BIGARADE OIL MD SCFC, ORANGE FLOWERABSOLUTE TUNISIA, ORANGE FLOWER WATER ABSOLUTE TUNISIA, ORANGE LEAFABSOLUTE, ORANGE LEAF WATER ABSOLUTE TUNISIA, ORRIS ABSOLUTE ITALY,ORRIS CONCRETE 15 PCT IRONE, ORRIS CONCRETE 8 PCT IRONE, ORRIS NATURAL15 PCT IRONE 4095C, ORRIS NATURAL 8 PCT IRONE 2942C, ORRIS RESINOID,OSMANTHUS ABSOLUTE, OSMANTHUS ABSOLUTE MD 50 PCT BB, PATCHOULI HEARTN^(o) 3, PATCHOULI OIL INDONESIA, PATCHOULI OIL INDONESIA IRON FREE,PATCHOULI OIL INDONESIA MD, PATCHOULI OIL REDIST, PENNYROYAL HEART,PEPPERMINT ABSOLUTE MD, PETITGRAIN BIGARADE OIL TUNISIA, PETITGRAINCITRONNIER OIL, PETITGRAIN OIL PARAGUAY TERPENELESS, PETITGRAIN OILTERPENELESS STAB, PIMENTO BERRY OIL, PIMENTO LEAF OIL, RHODINOL EXGERANIUM CHINA, ROSE ABS BULGARIAN LOW METHYL EUGENOL, ROSE ABS MOROCCOLOW METHYL EUGENOL, ROSE ABS TURKISH LOW METHYL EUGENOL, ROSE ABSOLUTE,ROSE ABSOLUTE BULGARIAN, ROSE ABSOLUTE DAMASCENA, ROSE ABSOLUTE MD, ROSEABSOLUTE MOROCCO, ROSE ABSOLUTE TURKISH, ROSE OIL BULGARIAN, ROSE OILDAMASCENA LOW METHYL EUGENOL, ROSE OIL TURKISH, ROSEMARY OIL CAMPHORORGANIC, ROSEMARY OIL TUNISIA, SANDALWOOD OIL INDIA, SANDALWOOD OILINDIA RECTIFIED, SANTALOL, SCHINUS MOLLE OIL, ST JOHN BREAD TINCTURE 10PCT, STYRAX RESINOID, STYRAX RESINOID, TAGETE OIL, TEA TREE HEART, TONKABEAN ABS 50 PCT SOLVENTS, TONKA BEAN ABSOLUTE, TUBEROSE ABSOLUTE INDIA,VETIVER HEART EXTRA, VETIVER OIL HAITI, VETIVER OIL HAITI MD, VETIVEROIL JAVA, VETIVER OIL JAVA MD, VIOLET LEAF ABSOLUTE EGYPT, VIOLET LEAFABSOLUTE EGYPT DECOL, VIOLET LEAF ABSOLUTE FRENCH, VIOLET LEAF ABSOLUTEMD 50 PCT BB, WORMWOOD OIL TERPENELESS, YLANG EXTRA OIL, YLANG III OILand combinations of these.

The colorants can be among those listed in the Colour IndexInternational by the Society of Dyers and Colourists. Colorants includedyes and pigments and include those commonly used for coloring textiles,paints, inks and inkjet inks. Some colorants that can be utilizedinclude carotenoids, arylide yellows, diarylide yellows, B-naphthols,naphthols, benzimidazolones, diazo condensation pigments, pyrazolones,nickel azo yellow, phthalocyanines, quinacridones, perylenes andperinones, isoindolinone and isoindoline pigments, triarylcarboniumpigments, diketopyrrolo-pyrrole pigments, thioindigoids. Carotenoidsinclude, alpha-carotene, beta-carotene, gamma-carotene, lycopene, luteinand astaxanthin, Annatto extract, Dehydrated beets (beet powder),Canthaxanthin, Caramel, β-Apo-8′-carotenal, Cochineal extract, Carmine,Sodium copper chlorophyllin, Toasted partially defatted cookedcottonseed flour, Ferrous gluconate, Ferrous lactate, Grape colorextract, Grape skin extract (enocianina), Carrot oil, Paprika, Paprikaoleoresin, Mica-based pearlescent pigments, Riboflavin, Saffron,Titanium dioxide, Tomato lycopene extract; tomato lycopene concentrate,Turmeric, Turmeric oleoresin, FD&C Blue No. 1, FD&C Blue No. 2, FD&CGreen No. 3, Orange B, Citrus Red No. 2, FD&C Red No. 3, FD&C Red No.40, FD&C Yellow No. 5, FD&C Yellow No. 6, Alumina (dried aluminumhydroxide), Calcium carbonate, Potassium sodium copper chlorophyllin(chlorophyllin-copper complex), Dihydroxyacetone, Bismuth oxychloride,Ferric ammonium ferrocyanide, Ferric ferrocyanide, Chromium hydroxidegreen, Chromium oxide greens, Guanine, Pyrophyllite, Talc, Aluminumpowder, Bronze powder, Copper powder, Zinc oxide, D&C Blue No. 4, D&CGreen No. 5, D&C Green No. 6, D&C Green No. 8, D&C Orange No. 4, D&COrange No. 5, D&C Orange No. 10, D&C Orange No. 11, FD&C Red No. 4, D&CRed No. 6, D&C Red No. 7, D&C Red No. 17, D&C Red No. 21, D&C Red No.22, D&C Red No. 27, D&C Red No. 28, D&C Red No. 30, D&C Red No. 31, D&CRed No. 33, D&C Red No. 34, D&C Red No. 36, D&C Red No. 39, D&C VioletNo. 2, D&C Yellow No. 7, Ext. D&C Yellow No. 7, D&C Yellow No. 8, D&CYellow No. 10, D&C Yellow No. 11, D&C Black No. 2, D&C Black No. 3 (3),D&C Brown No. 1, Ext. D&C, Chromium-cobalt-aluminum oxide, Ferricammonium citrate, Pyrogallol, Logwood extract,1,4-Bis[(2-hydroxy-ethyl)amino]-9,10-anthracenedionebis(2-propenoic)ester copolymers, 1,4-Bis[(2-methylphenyl)amino]-9,10-anthracenedione,1,4-Bis[4-(2-methacryloxyethyl) phenylamino] anthraquinone copolymers,Carbazole violet, Chlorophyllin-copper complex, Chromium-cobalt-aluminumoxide, C.I. Vat Orange 1,2-[[2,5-Diethoxy-4-[(4-methylphenyl)thiol]phenyl]azo]-1,3,5-benzenetriol,16,23-Dihydrodinaphtho [2,3-a:2′,3′-i] naphth [2′,3′:6,7] indolo [2,3-c]carbazole-5,10,15,17,22,24-hexone,N,N′-(9,10-Dihydro-9,10-dioxo-1,5-anthracenediyl) bisbenzamide,7,16-Dichloro-6,15-dihydro-5,9,14,18-anthrazinetetrone,16,17-Dimethoxydinaphtho (1,2,3-cd:3′,2′,1′-lm) perylene-5,10-dione,Poly(hydroxyethyl methacrylate)-dye copolymers(3), Reactive Black 5,Reactive Blue 21, Reactive Orange 78, Reactive Yellow 15, Reactive BlueNo. 19, Reactive Blue No. 4, C.I. Reactive Red 11, C.I. Reactive Yellow86, C.I. Reactive Blue 163, C.I. Reactive Red 180,4-[(2,4-dimethylphenyl)azo]-2,4-dihydro-5-methyl-2-phenyl-3H-pyrazol-3-one(solvent Yellow 18), 6-Ethoxy-2-(6-ethoxy-3-oxobenzo[b]thien-2(3H)-ylidene) benzo[b]thiophen-3(2H)-one, Phthalocyanine green,Vinyl alcohol/methyl methacrylate-dye reaction products, C.I. ReactiveRed 180, C.I. Reactive Black 5, C.I. Reactive Orange 78, C.I. ReactiveYellow 15, C.I. Reactive Blue 21, Disodium1-amino-4-[[4-[(2-bromo-1-oxoallyl)amino]-2-sulphonatophenyl]amino]-9,10-dihydro-9,10-dioxoanthracene-2-sulphonate(Reactive Blue 69), D&C Blue No. 9, [Phthalocyaninato(2-)] copper andmixtures of these.

Other than in the examples herein, or unless otherwise expresslyspecified, all of the numerical ranges, amounts, values and percentages,such as those for amounts of materials, elemental contents, times andtemperatures of reaction, ratios of amounts, and others, in thefollowing portion of the specification and attached claims may be readas if prefaced by the word “about” even though the term “about” may notexpressly appear with the value, amount, or range. Accordingly, unlessindicated to the contrary, the numerical parameters set forth in thefollowing specification and attached claims are approximations that mayvary depending upon the desired properties sought to be obtained by thepresent invention. At the very least, and not as an attempt to limit theapplication of the doctrine of equivalents to the scope of the claims,each numerical parameter should at least be construed in light of thenumber of reported significant digits and by applying ordinary roundingtechniques.

Notwithstanding that the numerical ranges and parameters setting forththe broad scope of the invention are approximations, the numericalvalues set forth in the specific examples are reported as precisely aspossible. Any numerical value, however, inherently contains errornecessarily resulting from the standard deviation found in itsunderlying respective testing measurements. Furthermore, when numericalranges are set forth herein, these ranges are inclusive of the recitedrange end points (e.g., end points may be used). When percentages byweight are used herein, the numerical values reported are relative tothe total weight.

Also, it should be understood that any numerical range recited herein isintended to include all sub-ranges subsumed therein. For example, arange of “1 to 10” is intended to include all sub-ranges between (andincluding) the recited minimum value of 1 and the recited maximum valueof 10, that is, having a minimum value equal to or greater than 1 and amaximum value of equal to or less than 10. The terms “one,” “a,” or “an”as used herein are intended to include “at least one” or “one or more,”unless otherwise indicated.

Any patent, publication, or other disclosure material, in whole or inpart, that is said to be incorporated by reference herein isincorporated herein only to the extent that the incorporated materialdoes not conflict with existing definitions, statements, or otherdisclosure material set forth in this disclosure. As such, and to theextent necessary, the disclosure as explicitly set forth hereinsupersedes any conflicting material incorporated herein by reference.Any material, or portion thereof, that is said to be incorporated byreference herein, but which conflicts with existing definitions,statements, or other disclosure material set forth herein will only beincorporated to the extent that no conflict arises between thatincorporated material and the existing disclosure material.

While this invention has been particularly shown and described withreferences to preferred embodiments thereof, it will be understood bythose skilled in the art that various changes in form and details may bemade therein without departing from the scope of the inventionencompassed by the appended claims.

What is claimed is:
 1. A method of protecting material processingequipment, the method comprising; conveying a biomass material under anelectron beam on a conveyor; and enclosing motor components in anequipment enclosure that does not surround the conveyor; and purging theenclosure with a gas that has been filtered to remove ozone.
 2. Themethod of claim 1 wherein the gas comprises air.
 3. The method of claim1, further comprising exchanging the gas in the equipment enclosure atan exchange rate of less than once every 10 minutes.
 4. The method ofclaim 1, wherein the conveyor is disposed within a vault.
 5. The methodof claim 4, wherein the vault also contains irradiating equipment. 6.The method of claim 1, wherein the gas is provided from within theenclosure.
 7. The method of claim 1, wherein the method further includesmoving the equipment enclosure to access the motor components.
 8. Themethod of claim 7, wherein the equipment enclosure is configured to bemovable.
 9. The method of claim 1, wherein the equipment enclosureincludes lead.
 10. The method of claim 1, wherein the exposure of themotor components to radiation is reduced by at least 10% as compared tothe radiation exposure that would occur without the equipment enclosure.11. The method of claim 10, wherein the exposure of the motor componentsto ionizing radiation is reduced by at least 20% as compared to theradiation exposure that would occur without the equipment enclosure. 12.The method of claim 11, wherein the exposure of the motor components toionizing radiation is reduced by at least 30% as compared to theradiation exposure that would occur without the equipment enclosure. 13.The method of claim 12, wherein the exposure of the motor components toionizing radiation is reduced by at least 50% as compared to theradiation exposure that would occur without the equipment enclosure. 14.The method of claim 13, wherein the exposure of the motor components toionizing radiation is reduced by at least 70% as compared to theradiation exposure that would occur without the equipment enclosure. 15.The method of claim 1 wherein the enclosure is radiation opaque.
 16. Themethod of claim 1, wherein the conveyor is a vibratory conveyor.
 17. Themethod of claim 1 wherein the gas is selected from the group consistingof oxygen reduced air, nitrogen, argon, helium, carbon dioxide, andmixtures thereof.
 18. The method of claim 16, further comprisingproviding a gap between the equipment enclosure and the vibratoryconveyor to accommodate movement of components of the vibratory conveyorduring use.